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        |   | Models | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |  
        | ME | IDW | 0.20 | 0.95 | 2.56 | 0.83 | -1.2 | 5.97 | -2.58 | 1.28 | -4.56 | 0.3 | -0.68 | 0.59 |  
        | TREND | 0.31         | 0.72         | 1.32         | 5.33 | 0.40 | 0.64         | 0.31         | 0.72         | 1.32         | 5.33 | 0.40 | 0.64 |  
        | OK | 0.22 | 0.97 | 2.54 | 1.48 | 0.35 | 6.73 | -2.23 | 2.66 | -3.78 | 0.75 | -0.65 | 0.58 |  
        | SPLINE | 0.42 | 1.16 | 3.65 | 2.59 | 1.27 | 9.98 | -0.94 | 4.5 | -3.3 | 1.02 | -0.38 | 0.7 |  
        | REGRESSION | 0.32 | 1.04 | 2.3 | 0.36 | -1.51 | 6.15 | -3.56 | -0.23 | -6.09 | -0.57 | -0.75 | 0.7 |  
        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        | MAE | IDW | 0.84 | 1.56 | 4.46 | 5.34 | 6.84 | 11.41 | 12.68 | 9.98 | 6.47 | 3.1 | 1.52 | 1.15 |  
        | TREND | 1.06 | 2.09 | 5.24 | 6.10 | 6.34 | 11.89 | 10.93 | 8.44 | 7.53 | 3.17 | 1.67 | 1.33 |  
        | OK | 0.84 | 1.89 | 5 | 4.85 | 4.57 | 8.15 | 8.18 | 7.06 | 4.8 | 1.63 | 1.41 | 1.18 |  
        | SPLINE | 0.97 | 1.81 | 7.29 | 6.99 | 7.04 | 12.18 | 12.57 | 9.71 | 6.68 | 2.79 | 1.51 | 1.47 |  
        | REGRESSION | 1.05 | 1.98 | 4.94 | 5.86 | 5.03 | 7.46 | 6.07 | 4.6 | 7.41 | 2.92 | 1.72 | 1.3 |  
        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        | RMSE | IDW | 1.19 | 1.94 | 5.65 | 6.53 | 8.56 | 13.50 | 15.47 | 12.72 | 8.23 | 3.51 | 1.71 | 1.35 |  
        | TREND | 1.28 | 2.22 | 8.13 | 8.88 | 8.52 | 15.01 | 15.80 | 10.52 | 8.23 | 3.88 | 1.88 | 1.79 |  
        | OK | 1.18 | 2.16 | 6.16 | 6.21 | 5.54 | 10.78 | 9.75 | 8.62 | 6.05 | 2.18 | 1.65 | 1.37 |  
        | SPLINE | 2.22 | 8.13 | 8.88 | 8.52 | 15.01 | 15.80 | 10.52 | 8.23 | 3.88 | 1.88 | 1.79 | 2.22 |  
        | REGRESSION | 1.27 | 2.32 | 6.16 | 6.63 | 6.10 | 9.47 | 8.33 | 7.39 | 9.21 | 3.51 | 2.08 | 1.53 |  |