Because Bush signed a six-year "military service obligation," he was required to attend at least 44 inactive-duty training drills each fiscal year beginning July 1. But Bush's own records show that he fell short of that requirement, attending only 36 drills in the 1972-73 period, and only 12 in the 1973-74 period. The White House has said that Bush's service should be calculated using 12-month periods beginning on his induction date in May 1968. Using this time frame, however, Bush still fails the Air Force obligation standard.

Moreover, White House officials say, Bush should be judged on whether he attended enough drills to count toward retirement. They say he accumulated sufficient points under this grading system. Yet, even using their method, which some military experts say is incorrect, U.S. News 's analysis shows that Bush once again fell short. His military records reveal that he failed to attend enough active-duty training and weekend drills to gain the 50 points necessary to count his final year toward retirement.

The U.S. News analysis also showed that during the final two years of his obligation, Bush did not comply with Air Force regulations that impose a time limit on making up missed drills. What's more, he apparently never made up five months of drills he missed in 1972, contrary to assertions by the administration. White House officials did not respond to the analysis last week but emphasized that Bush had "served honorably."