What is the average rate of change in U.S. population from July 1,19881,1988 to July 1,19941,1994?

Date	Nat'I. Pop.	Pop. Chng.
July1,1999July1,1999	272,690,813272,690,813	2,442,8102,442,810
July1,1998July1,1998	270,248,003270,248,003	2,464,3962,464,396
July1,1997July1,1997	267,783,607267,783,607	2,555,0352,555,035
July1,1996July1,1996	265,228,572265,228,572	2,425,2962,425,296
July1,1995July1,1995	262,803,276262,803,276	2,476,2552,476,255
July1,1994July1,1994	260,327,021260,327,021	2,544,4132,544,413
July1,1993July1,1993	257,782,608257,782,608	2,752,9092,752,909
July1,1992July1,1992	255,029,699255,029,699	2,876,6072,876,607
July1,1991July1,1991	252,153,096252,153,096	2,688,6962,688,696
July1,1990July1,1990	249,464,396249,464,396	2,645,1662,645,166
July1,1989July1,1989	246,819,230246,819,230	2,320,2482,320,248
July1,1988July1,1988	244,498,982244,498,982	2,210,0642,210,064
July1,1987July1,1987	242,288,918242,288,918	2,156,0312,156,031
July1,1986July1,1986	240,132,887240,132,887	2,209,0922,209,092
July1,1985July1,1985	237,923,795237,923,795	2,098,8932,098,893
July1,1984July1,1984	235,824,902235,824,902	2,032,9082,032,908
July1,1983July1,1983	233,791,994233,791,994	2,127,5362,127,536
July1,1982July1,1982	231,664,458231,664,458	2,198,7442,198,744
July1,1981July1,1981	229,465,714229,465,714	2,241,0332,241,033
July1,1980July1,1980	227,224,681227,224,681	2,169,1942,169,194