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

Table 2

The fitting value of Yinchuan Plain groundwater depth by DGGM (1,1) model (unit: m).

Month	Year
	2015	2016	2017	2018
1	2.03	1.97	2.11	2.18
2	2.38	2.51	2.45	2.62
3	2.56	2.74	2.79	2.91
4	2.64	2.67	2.84	3.09
5	2.56	2.78	3.07	3.24
6	1.83	2.08	2.14	2.28
7	1.64	1.67	1.89	2.07
8	1.61	1.74	1.67	1.78
9	1.82	1.93	2.09	2.26
10	2.33	2.41	2.62	2.77
11	2.45	2.67	2.91	3.05
12	1.31	1.45	1.63	1.8
MAPE	3.94