The Effect of Lead Time toward Supply Control at Paku Payung Club

The background of this research is that the company experienced delays in receiving ordered goods due to several reasons, namely the limited activity of suppliers in producing ordered goods, and also delays in transportation in the delivery of goods orders resulting in delays in the supply of goods to the company. The lead time that the company has estimated is 168 hours; due to limited transportation, receiving orders has been delayed, especially in July 2020, which was 192 hours, and in March 2021, which was 144 hours. This study aims to determine the effect of lead time on inventory control of hijab label accessories at Paku Payung Club (PPC). Inventory control is one of the management functions that are very important to determine the level of inventory that must be maintained so that inventory does not run out of goods or otherwise experience excessive inventory. The research was conducted based on data on lead time and company control from July 2020 to July 2021. The research method used is an associative descriptive research method, then the type of quantitative data and ratio scale. Then it is processed using the classical assumption test, regression test, simple correlation test, coefficient of determination test, partial significant hypothesis test (t-test), and simultaneous hypothesis test (f test). The results show that there is an effect of lead time on inventory control at Paku Payung Club, with a correlation coefficient that has a powerful influence. This research is expected to be input for the Paku Payung Club business manager in production planning thus that the business can run effectively and efficiently.


Introduction
The pandemic forced everyone to activate survival mode.All lines are trying to adapt to stay alive during a crisis, including the fashion industry (Brydges et al., 2021).In their report for Business of Fashion, Angelica & Huaranga (2020) said that the fashion industry was in a high-alert position at the beginning of the year.So it is predicted that the fashion industry will experience a crisis and its executives are already pessimistic about 2020.The Business of Fashion notes that nearly three-quarters of the registered fashion companies have experienced losses.There was a 34% decline in sales in January-March 2020 when the Covid-19 pandemic entered Indonesian territory.
At the end of the year, based on an analysis of the McKinsey Global Fashion Index, the profit rate fell by 90 percent compared to 2019.
Inventory of goods and materials is crucial as a cog in the business.Moreover, in a pandemic situation, companies must be able to make or formulate strategies to manage their inventory to avoid losses (Anggadwita et al., 2022).The crisis caused unstable market conditions and caused uncertainty supply chain (Alamanda et al., 2022).Disruptions to supply and demand that occur continuously result in an uncontrolled supply of goods (Singh et al., 2021).Inventory is an essential part of companies, especially trading companies, and is often an estimate that must be taken into accounts, such as uncertain prices, significant working capital, and maintenance of these inventories (Atseye et al., 2016).If there is no inventory, the company will not be able to fulfill its customers' wishes, which will have a destructive impact because the company will indirectly lose the customers it should have.Therefore, companies must be able to carry out good planning, control and supervision so that production is not hampered.If there is an excess of inventory, it can cause a buildup of inventory in the warehouse so that there is a risk of damaged, obsolete inventory, and opening up opportunities for irregularities or even theft of merchandise inventory (Robinson, 1990).Based on interviews with the Garment Purchase Staff, the problems related to delays in receiving ordered goods are the limited activity of suppliers in producing ordered goods and delays in transportation in sending goods orders resulting in delays in inventory goods reaching the company.Ordering accessories for hijab labels at Paku Payung Club during the Covid 19 pandemic was carried out in different amounts and at the same time interval; this can be seen in Table 1.Table 1 shows that there were fluctuations in the number of incoming and outgoing goods and the availability of goods.Therefore, Paku Payung Club hopes to minimize delays by providing sufficient safety stock so as not to experience a shortage of hijab label supplies in carrying out the production process during the Covid-19 pandemic.The company must be able to correctly estimate the lead time and the number of orders for hijab labels so that the production process is not hampered.Based on the research background, this study aims to determine how the effect of lead time on inventory control of hijab labels at Paku Payung Club.

Literature Review
Lead time is the time between placing an order and receiving the ordered goods, referred to as lead time or delivery time, which can be short, such as a few hours, or longer, such as several months (Assauri, 2016).According to Heizer & Rander (2015) The time the goods are waiting in the warehouse or factory.States that inventory is merchandise that is stored and then resold in the company's regular operations and materials contained in the production process or that have been stored for a purpose (Aulia, 2020).
State that Inventory is a stock or deposit of goods stored by the company in inventories related to the business being carried out (Stevenson & Choung, 2015).Bendig et al. (2018) stated that inventory is current wealth in raw material inventory, work in process, and finished goods.Trading companies always buy their merchandise as goods ready for resale, and manufacturing companies produce goods for sale to trading companies.Based on some of the definitions above, it can be concluded that Inventory is an item stored in the company's warehouse or goods ready to be sold to the company's consumers.
According to Ogbo et al. (2014), effective inventory control is where the company can provide sufficient Inventory in a period and anticipate price changes, store Inventory at minimum cost, and ensure the capital invested in Inventory is consistent.The purpose of inventory control is (1) To be able to meet consumer needs or requests quickly (satisfy consumers); (2) To maintain production continuity or to keep the company from running out of stock; (3) To maintain and increase the company's sales and profits if possible; (4) Keeping buyers small can be avoided because it can incur high ordering costs; (5) Ensure that storage in emplacements is not massive (Fithri et al., 2019).
The theory that becomes the relationship between Lead Time and Inventory Control According to Damayanti (2012)

Methodology of Research
The approach used in this research is quantitative.The method used is descriptive and associative.This study used the descriptive method to explain the lead time and inventory control of hijab label accessories at Paku Payung Club during the Covid 19 pandemic.The data then analyzed using simple linear regression with the help of software SPSS 26.Lead Time for ordering hijab label at Paku Payung Club is shown in Table 2. From Table 2, it can be seen that the most significant delay in receiving hijab label accessories occurred in July 2020, which was 192 hours, and in March 2021, which was 144 hours.That was because the company had just ordered hijab labels, and the number of orders tended to be more significant.

Normality Test
In this study the normality test used is the normal probability plot test (Normal P-P Plot), which is an effective alternative to detect whether the regression model to be analyzed in a study is normally distributed or not.The Probability Plot could be seen in Figure 2.

Lead Time Inventory Control
Figure 2. Probability Plot

Linierity Test
The linearity test aims to determine whether two variables have a linear relationship or not significantly.This test is usually a prerequisite in correlation or linear regression analysis.The significance level used in this study is α = 0.05.The way to determine whether the two variables are linear is by looking at the significant value in the Deviation from the Linearity line.If the significance value (Sig.)> 0.05, it can be concluded that between the two variables, there is a linear relationship.Based on the Table 3, it is known that the significance value is (0.154) > 0.05.
It can be concluded that between the two variables, there is a linear relationship

Heteroscedasticity Test
The heteroscedasticity test aims to test whether there is an inequality of in the regression model from one residual observation to another.The heteroscedasticity test appears when the errors or residuals of the observed model do not have a constant variance from one observation to another.The heteroscedasticity test can be seen with a scatter plot where the distribution of the points generated is formed randomly, does not form a specific pattern, and the direction of the distribution is above or below the number 0 on the Y axis.Based on the Scatterplot on Figure 3, it can be obtained that the data points spread above and below the number 0; the dots do not gather only above or below; the spread of the data points does not form a wavy pattern.It widens, then narrows, and widens again and the distribution of data points is not patterned.Therefore, it can be concluded that there are no symptoms of heteroscedasticity.

Regression Test
In this study a simple linear regression analysis was used to test the effect of lead time on inventory control of hijab label accessories at Paku Payung Club (PPC) during the Covid 19 pandemic.The results of the simple linear regression can be seen in Table 5.The intercept or (Constant) is -7374.384; the value of the constant is negative, meaning that if the lead time score is considered absent or equal to zero, then the inventory control score will decrease.According to Mendenhall (2011: 99), the negative constants may occur and not be a problem or could be ignored for the regression equation during the regression equation meets the criteria of normality and linearity assumptions.This study tried to use a least squares model to predict Y for a value of X, so the highlight is the regression coefficient or the slope.Negative intercept values are the effect of out-of-range sample data (called extrapolation).As a result, the intercept will not always have a practical interpretation.
The value of the regression coefficient X is 127.155,meaning that if the lead time value increases by one point, it will increase inventory control by 127.155 x 100% = 12715.5%.The coefficient value has a positive sign (+), so it can be said that lead time positively affects inventory control.

Correlation Test
The correlation coefficient is the number of the strong relationship between two or more variables.
For the basis of decision-making, if the significance value is <0.05, it is correlated, and vice versa; if the significance value is > 0.05, it is not correlated.The correlation result could be seen on Table 6.It can be obtained a significance value (0.013) <0.05, thus it can be concluded that there is a relationship between lead time and inventory control.In addition, the value of the earson correlation is 0.861, so it can be obtained that the correlation is very strong.

Coefficient of Determination
The coefficient of determination (R²) basically measures how far the model's ability to explain the variation of the independent variables.To find out the influence of the two variables, namely lead time on inventory control, a coefficient of determination test was carried out.Based on calculations using SPSS version 26.0, it is known that the coefficient of determination on Table 7.It is known that t table = (a/2; n-k-1) = (0.05/2;7-1-1) so it is known to find t table (0.025;5) = 0.727.With this acquisition, the results can be obtained: Lead time has a partial positive effect on Inventory Control because t calc (3.783) > t table (0.727).
Simultaneous test (f-test) is used to determine the significant effect of the independent variables together on the dependent variable.Based on calculations using SPSS version 26.0, it is known that the value of the simultaneous test (f-test) is shown on Table 9.Based on Table 9, it is known that f table = (k ; n -k) = (1 ; 7 -1) = (1; 66) = 5.99 Because the value of f calc (14.312) > f table (5.99) then the lead time simultaneously a positive effect on inventory control.Paku Payung Club accessories include OPV plastic, hood labels, size labels, hangtags, buttons, and crackles.Each accessory comes from a different supplier.Here the author chooses to examine the hijab label because it has experienced delays in its delivery caused by several things.The company predicts that the lead time for each order of hijab label accessories is 168 hours.In this study, there were waiting several times for Paku Payung Club hijab label accessories which experienced significant delays every month, so the average lead time within one year during the Covid-19 pandemic was 240 hours.The lead time experienced delay occurred in July 2020; the company experienced a delay in receiving the hijab label accessories, which was 360 hours or late (192 hours) from the time estimated by the company.In September 2020, the company experienced a delay in receiving hijab label accessories, namely for 264 hours or later (96 hours) than the time estimated by the company.The company had to queue to order hijab label accessories, so it did not match the estimated time.In March 2021, the company experienced a delay in receiving hijab label accessories, namely for 312 hours or later (144 hours) than the time estimated by the company; this was because the company had to queue for hijab label accessories, so it did not match the estimated time.By the theory according to Indrajit in Faizol (2021:24), supply chain management, the concept of lead time can be viewed from two sides, namely the customer or consumer side and the supplier side.The company must be able to anticipate all possibilities by developing a strategy, such as preparing an ideal safety stock both from the consumer side and from the supplier side so that the production process is not hampered.
In this study, the company ordered Paku Payung Club (PPC) hijab label accessories in different quantities; for example, in July 2020, the company ordered 30,000 pcs of hijab labels and produced 9,310 pcs, so there were 20,690 available hijab labels.In September 2020, the company again ordered hijab labels with a 2-month reorder time of 33,000 pcs and produced 24,954 scarves so that there were 28,736 available hood labels.In December 2020, the company again ordered hijab labels with a 3-month reorder time of 15,000 pcs and produced 10,653 pcs, so there were 33,083 headhijab labels available.In February 2021, the company again ordered hijab labels with a 2-month reorder of 50,000 pcs and produced 41,879 headhijab labels to make 41,204 pcs available.In March 2021, the company again ordered hijab labels with a monthly reorder time of 38,000 pcs and produced 31,828 pcs, so there were 41,204 available hijab labels.Produced 7,670 pcs so that there were 43,534 available hijab labels.In July 2021, the company ordered hijab labels again with a 1-month reorder of 24,000 pcs and produced 15,622 pcs to make 51,192 hijab labels available.
According to Vikaliana et al. (2020: 8), inventory control is an essential management function for determining inventory levels that must be maintained so that supplies do not run out of goods or, vice versa, experience excessive inventory.Therefore, the company must develop a strategy of ideal safety stock because if the inventory is too much, there will be many costs incurred.Based on the results of the correlation test, it was obtained a Significance value (0.013) <0.05, so it can be concluded that there is a relationship between lead time and inventory control.In addition, the value of the Pearson correlation is 0.861 or 86%, so the result can be obtained that the correlation is very strong or perfect.
Then the coefficient of determination test results is known to obtain an R Square value of 0.741, where the magnitude of the influence of lead time on inventory control is 74.1%, and the remaining 25.9% is influenced by other factors not examined.Then, based on the partial test (t test), Lead Time has a partial positive effect on Inventory Control because t count (3.783) > t table (0.727).
The previous chapter explained that the hypothesis proposed was "lead time has a positive effect on controlling the supply of hijab label accessories at Paku Payung Club during the Covid-19 pandemic".After testing these two variables, it can be seen that lead time positively affects inventory control.These results can be seen in the linear regression test, which obtained favorable results.The higher the lead time, the more inventory control increases.Then in the correlation test, the coefficient of determination test obtained positive results, and the partial test (t-test) lead time positively affected inventory control.

Conclusion
Based on the acquisition of the lead time channel for hijab label accessories at Paku Payung Club during the Covid-19 pandemic for one year starting from July 2020 to July 2021, it tends to experience delays, especially in July 2020 (192 hours) and March 2021 (144 hours) in ordering hijab label accessories.However, the next month experienced a delay but not too significant.Even though the ordering of accessories for hijab labels experienced delays, the company was able to anticipate this by holding safety stock.The company ordered hijab labels in different quantities and with different reorder point times.It can be said that the company has not been effective and efficient in minimizing the costs incurred to control the supply of hijab label accessories.The last, it can be said that lead time has a positive effect on inventory control, and it can be concluded that there is a relationship between lead time and inventory control.
Based on the results, this study provides some suggestions.It is better if the company plans orders by planning the number and time of reordering (reorder point), so that the company can handle the production process.If ordering accessories for hijab labels is in the queue, the company can anticipate them.The second suggestion is that the company should be ready to store safety stock to make it easier to manage or control its inventory.
Regarding managing the supply of accessories for hijab labels at Paku Payung Club (PPC) during the Covid 19 pandemic, the third recommendation is, the company should calculate the ideal number of orders to reduce costs incurred for ordering hijab labels.
Payung Corp is a company engaged in the fashion industry.The Paku Payung Corp company was established in 2015 in Cigugur Girang, Parongpong District, West Bandung Regency, which is known as a company that has successfully collaborated and collaborated with parties throughout Indonesia and Southeast Asia.One of the company's missions is to have a perspective on internal business processes, including a partnership focus, product focus, social focus, and environmental focus.Paku Payung Corp oversees several fashion brands, including Paku Payung Club (PPC), Zeta Outfit, Oshiby.ID and others.One fashion brand that is quite popular among Indonesians is Paku Payung Club (PPC).Paku Payung Club (PPC) produces Muslim clothing for Indonesian families.In just four years, Paku Payung Club (PPC) has succeeded in becoming the market leader in providing Muslim clothing for families made in Indonesia.Paku Payung Corp currently has as many as 25+ suppliers who work together according to the needs of alternative Paku Payung Corp brands.(Source: http://pakupayungcorp.com/).
in the implementation of raw material supplies for the implementation of the production process of a company, several factors will affect the supply of raw materials, where the factors are these factors are related to each other.The various factors include (1).Raw Material Estimation; (2).Material Prices; (3).Inventory Costs; (4).Purchase Policy; (5).Material Usage; (6).Lead Time; (7).Purchasing Model; (8).Safety Inventory; (9).Repurchase.Based on the literature review and empirical gap, the research paradigm is displayed on Figure 1.

Table 1 .
Average Inventory of Hijab labels at Paku Payung Club Period 2020 -2021

Table 3 .
ANOVA .If the significance value is ≤ 0.05, there is autocorrelation From Table4, the Asymp Sig value is obtained.(0.363) > 0.05, so it can be concluded that there is no autocorrelation symptom.
Run Test is used to see whether the residual data occurs randomly or not systematically.If the residual is random, the significance value is above 5%.It can be stated that there is no correlation between the residuals, or it can be stated that there are no symptoms of autocorrelation.1.If the significance value is ≥ 0.05, there is no autocorrelation.2

Table 5 .
Coefficient of Regression

Table 7 .
Coefficient of DeterminationThe partial test (t test) is used to determine individual significance, where this test shows how far the independent variable partially influences the dependent variable.Based on calculations using SPSS version 26.0, it is known that the partial test value (t-test) is shown on Table8.

Table 9
It does not mean that the company has to provide a small amount of safety stock because if the inventory is deficient, the company cannot carry out the production process Based on the study's results, lead time positively affects controlling hijab label accessories at Paku Payung Club (PPC) during the Covid-19 pandemic.The results of the linear regression test obtained a regression coefficient X of 127.155, meaning that if the lead time value increases by one point, it will increase inventory control by 127.155 x 100% = 12715.5%.The output of the linear regression is known to have a sign (+), which means that it can be said that lead time has a positive effect on inventory control.