A principal cause of this unbalanced population loss appears to be rejection of core city education systems, evidenced by the fact that there was a disproportionate loss in school age population. A major factor in many areas was the implementation or threat of forced busing, as many parents perceived it necessary to move to the suburbs to ensure their childrens safety and education quality. During the 1970s, public school enrollments dropped 3.6 million, while the number of school children bused to school rose 3.5 million, a negative ratio never previously or since achieved.

At a time when smart growth and new urbanist theorists decry the fact that so many school children no longer walk to school, it is well to remember how this all started. By conscious public policy, school children were prohibited from walking. They were assigned to schools under forced busing regimes that were so far away that they could not possibly walk. Many parents who were not able to move to the suburbs began driving their kids to school out of fear for their safety. In the end, major elements of both the African-American and White communities undertook efforts to bring forced busing to a not to early end.

The following table provides a counterfactual analysis of what core city population would have been during the disasterous 1970s if change in population had been balanced between adults and school age children at the same ratio as the rest of the nation. It is estimated that the cities would have lost only 650,000 people, rather than the actual 2.1 million.

Metropolitan Area	Core City	1970-Actual Population	1980-Actual Population	Exhibit: See Note: 1980-Calculated Population	1980-Estimate: If No Education Exodus	Difference
Atlanta	Atlanta	497	425	454	454	29
Baltimore	Baltimore	906	789	845	845	57
Boston	Boston	641	563	596	596	33
Buffalo	Buffalo	463	358	393	393	35
Chicago	Chicao	3,363	3,005	3,149	3,149	144
Cincinnati	Cincinnati	453	385	415	415	29
Cleveland	Cleveland	751	574	606	606	32
Columbus	Columbus	539	565	583	583	18
Denver	Denver	515	492	529	529	37
Detroit	Detroit	1,511	1,203	1,276	1,276	73
Dallas-Ft. Worth	Fort Worth	393	385	402	402	17
Dallas-Ft. Worth	Dallas	844	904	930	930	26
Hartford	Harford	158	136	140	140	4
Houston	Houston	1,232	1,595	1,600	1,600	5
Indianapolis	Indianapolis	745	701	749	749	49
Kansas City	Kansas City	507	448	483	483	35
Los Angeles	Los Angeles	2,816	2,967	3,048	3,048	81
Miami-Ft. Lauderdale	Miami	335	347	354	354	7
Milwaukee	Milwaukee	717	636	683	683	47
Minneapolis-St. Paul	Minneapolis	434	371	403	403	32
Minneapolis-St. Paul	St. Paul	310	270	295	295	24
Norfolk-Hampton	New Orleans	593	558	589	589	31
New Orleans	New Orleans	308	267	286	286	19
New York	New York	7,895	7,072	7,313	7,313	241
Pittsburgh	Pittsburgh	520	424	466	466	42
Philadelphia	Philadelphia	1,949	1,688	1,788	1,788	100
Phoenix	Phoenix	582	789	781	789	0
Portland	Portland	382	366	390	390	24
Providence	Providence	179	157	164	164	7
Sacramento	Sacramento	254	276	269	276	0
San Antonio	San Antonio	654	786	785	786	0
San Diego	San Diego	697	876	875	876	0
Seattle	Seattle	531	494	532	532	39
San Francisco	San Francisco	716	679	708	708	29
St. Louis	St. Louis	622	453	508	508	55
Tampa-St. Petersburg	St. Petersburg	216	239	239	239	0
Tampa-St. Petersburg	Tampa	278	272	284	284	12
Washington	Washington	757	638	684	684	46
Total		35,263	33,152	34,595	34,611	1,459
			(2,111)		(652)
Calculated population is the residents the city would have had if the adult population change had been associated with a school age child change consistent with the national rate.
1980-Estimate: If No Education Exodus column: This is the final estimate of what the population of the city would have been in the 1980 census if the number of children per moving adult had been the same as the national ratio between 1970 and 1980. In the few cases where the Calculated Population (above) is less than the actual 1980 figure, the actual 1980 figure is used. These cases are generally very fast growing cities that had large expanses of undeveloped land (Phoenix, Sacramento, San Antonio and San Diego) that contained a larger percentage of metropolitan growth (the exception is St. Petersburg, where the school age to population ratio was already very low in 1970, owing to that city's role as a retirement center).