RMSE	Standard deviation	Average	Temperature	Geothermal measure
8.61	8.3	−2.3	150.21	Na/K (ppm) [22]
9.4	8.32	−4.37	149.76	Na/K (mol/l) [18]
10.08	8.56	5.32	164.64	Na/K (ppm) [21]
10.2	8.32	5.9	154.82	Na/K (ppm) [16]
10.35	10.13	2.1	131.29	Na/K (ppm) [21]
11.52	11.5	−0.66	121.02	Na/K (ppm) [19]
11.52	11.5	−0.79	120.92	Na/K (mol/l) [9]
13.3	10.96	7.53	131.63	Na/K (mol/l) Mirchard (1979)
13.91	8.3	11.16	161.62	Na/K (mol/l) [19]
14.37	8.3	11.72	161.98	Na/K (ppm) [20]
14.53	14.13	3.39	112.94	Na/K (mol/l) [9]
18.86	12.7	13.95	154	Na/K/Ca (mol/l) [9]
24.25	8.51	22.71	180.53	Na/K (mol/l) [23]
24.38	8.51	22.85	180.62	Na/K (mol/l) [24]
40	9.16	−38.94	129	Na/K (mol/l) [9]
46.44	9.06	−45.54	121.69	Na/K (mol/l) [18]
47.04	14.83	44.64	148.89	Na/K (mol) [25]
61.08	18.23	−58.29	117.01	Na-K-Ca [26]
106.31	12.5	105.57	163.19	[26]
142.93	22.65	−141.12	84.2	Mg/k² (ppm) [23]
144.64	22.66	−142.85	82.76	K/Mg (ppm) [24]
156.96	22.26	−155.37	59.17	Mg/k² (mol/K∙gw) [18]