Sales forecasting and production planning of acid and distilled water by entrepreneurs in Charoen Mueang Subdistrict, Phan District, Chiangrai Province

Abstract

  This research aimed to: 1) study the sales data of acid and distilled water by entrepreneurs in Charoen Mueang Subdistrict, Phan District, Chiangrai 2) forecast and select sales forecasting techniques for acid and distilled water, and 3) propose planning recommendations for the production by entrepreneurs in Charoen Mueang Subdistrict, Phan District, Chiangrai. The study employed both qualitative and quantitative research methods, with data collected from document studies and structured interviews, focusing on providing benefits to the entrepreneurs. The primary informant group was the by entrepreneurs in Charoen Mueang Subdistrict, Phan District, Chiangrai. The findings revealed that the three-year sales data showed variations according to different festive periods. Therefore, the researcher employed three forecasting methods: 1) simple moving average, 2) weighted moving average, and 3) exponential smoothing, and selected the forecasting technique. The exponential smoothing method had the lowest absolute percentage error, with acid having an average error rate of 44%. The economic order quantity (EOQ) analysis indicated 19,341 bottles with an optimal order frequency of 10 times per year and an inventory level of 1,800 bottles, reducing raw material ordering costs by 4,712.50 baht. For distilled water, the error rate was 30%, with an Economic Order Quantity of 1,800 bottles, an order frequency of 7 times per year, and an inventory level of 1,620 bottles, reducing raw material ordering costs by 6,597.5 baht and total raw material costs by 147.67 baht per year. Entrepreneurs can use this information to plan the production of acid and distilled water to enhance production efficiency.