It's the economy, stupid

Percent change in GDP (adjusted for inflation)

1. Franklin Roosevelt (D) ('40-'44) +74.69
2. Franklin Roosevelt (D) ('32-'36) +34.63
3. Lyndon Johnson (D) ('64-'68) +21.81
4. Harry Truman (D) ('48-'52) +21.00
5. John Kennedy (D) ('60-'64) +19.86
6. Franklin Roosevelt (D) ('36-'40) +19.33
7. Bill Clinton (D) ('96-'00) +17.87
8. Ronald Reagan (R) ('84-'88) +15.98
9. Jimmy Carter (D) ('76-'80) +13.67
10. Bill Clinton (D) ('92-'96) +13.53
11. Dwight Eisenhower (R) ('52-'56) +13.45
12. Ronald Reagan (R) ('80-'84) +12.63
13. Richard Nixon (R) ('68-'74) +12.38
14. Dwight Eisenhower (R) ('56-'60) +10.91
15. Gerald Ford (R) ('74-'76) +10.62
16. George H. W. Bush (R) ('88-'92) +8.81
17. George W. Bush (R) ('00-'04) +8.75
18. Gorge W. Bush (R) ('04-'08) +2.00*
19. Harry Truman (D) ('45-'48) -9.04
20. Herbert Hoover (R) ('29-'32) -25.60

*Based on an estimate of economic performance in fourth quarter '08

Roosevelt's numbers for his third term are an aberration caused by World War II. Likewise, Truman's numbers for his first term (when he took over after FDR's death) reflect the post war recession. Other than that, pretty telling stuff.