TABLE 12. Monthly water budget for Lake Helene near Polk City, 1902

 Items of inflow Items of outflow
 Change in volume
 Change In Runoff (vV)
 Average stage Precipitation from land Seepage Evaporation Pumpage
 Lake stage surface during month (P) (R) (Be) (E) (Pu) -mutd'
 Month at beginning area -- omputed Observed
 1982 of month (acres) (ft) (in (In) (ac-ft) (in) (ac-ft) (in) (ac-ft) (In) (ac-ft) (In) (ac-ft) (ac-ft) (ac-ft)
 (1) (2) (8) (4) (5) (6) (7) (8) (9) (10) (11) ( ) ( (18) (14) (15) (16) (17)

 Jan. 141.464 56.2 -0.182 -2.18 1.28 5.99 0.11 0.52 -0.98 -4.36 2.88 18.25 -11.1 -10.2
 Feb. 141.282 55.6 .878 -4,54 .84 1.58 -1.08 -7.78 2.98 18.81 -20.0 -21.0
 Mar. 140.904 54.7 .859 -4.81 8.48 15.86 -2.17 -9.89 5.61 26.57 0.22 1.00 -20.6 -19.6
 Apr. 140.545 58.8 .485 5.22 1.69 7.58 .00 -4.04 5.46 24.48 -20.9 -28.4
 May 140.110 58.8 + .070 + .84 7.29 82.88 1.38 6.18 -2.17 -9.64 5,59 24.83 + 4.0 + 8.7
 June 140.180 53.6 + .160 +1.92 6.67 20,79 .44 1.97 .80 -1.84 4.48 20.01 .50 2.28 + 8.2 + 8.6
 July 140.840 58.7 .088 -1.06 6.76 25.73 .36 1.01 .81 -1.39 5.69 25.46 1.84 6.00 5.5 4.7
 Aug. 140.22 68.9 + .808 +8.70 6.52 20,20 .R8 4.40 + .62 +2.78 4.44 10.94 +16.5 +16.6
 Sept. 140.560 54.2 .062 .74 2.99 18.50 .06 .27 + .90 +4.06 4.97 22.45 4.6 8.4
 Oct. 140.498 58.8 .882 -8.98 1.98 8.88 .27 1.21 .81 -1.39 4.06 22.24 1.01 4.53 -18.1 -17.9
Nov. 140.166 58.0 ,286 -38.43 1.40 6.18 .19 .84 + .80 +1.32 3.62 15.99 1.65 7.20 -14.9 -15.2
sec. 189.880 52.2 .648 -7.78 .24 1.04 + .81 +1.35 2.47 10.74 5.76 25.06 -88.4 -88.8
Jan. 189.282
 9 8.63 177.80 3.79 16.95 -0.64 -80.82 58.10 288.82 10.48 46.11 -120.4 -120.8
Year

 Computed change in volume Precipitation + runoff + seepage evaporation pumpage.
 Observed change in volume = change in stage during month X average surface area.