A Grey Seasonal Index Model for Forecasting Groundwater Depth of Ningxia Plain

Table 10

Annual fitting value of groundwater depth in Weining Plain (unit: m).

Year	Actual value	Fitting value
2014	21.24	21.24
2015	21.54	21.52
2016	20.69	20.66
2017	21.19	21.18
2018	22.31	22.28
MAPE		0.10