Model of Automobile Parts Sale Prediction Based on Nonlinear Periodic Gray GM(1,1) and Empirical Research

Table 5

Comparison of the results of the two models (unit: ten thousand).

Month and year	Actual value	Single GM(1,1) forecasting model predicted value	Gray GM(1,1) nonlinear periodic model predicted value
Jan, 2018	18.16	17.11	18.15
Feb, 2018	18.10	16.76	18.10
Mar, 2018	20.45	17.61	20.62
Apr, 2018	18.12	18.50	18.08
May, 2018	22.21	19.44	22.28
Jun, 2018	22.14	20.42	22.34
Jul, 2018	16.32	21.46	16.05
Aug, 2018	20.89	22.54	20.89
Sept, 2018	27.85	23.69	27.92
Oct, 2018	27.41	24.89	27.27
Nov, 2018	24.51	26.15	24.40
Dec, 2018	25.91	27.47	25.99