71.   Aetna executives attribute some of the tension to cultural changes at the company that began only a few years ago.

72.   All that starts to change at the tipping point, he said.

73.   All that was despite significant changes at Triarc in the last couple of years.

74.   Brown said Hill would take the place of Ivan Williams, a move that indicates the possibility of a change at starting tailback.

75.   Burr said that despite the added stress from the service changes at so many airlines, travelers would eventually applaud them.

76.   But advertisers think the audience age change at news networks is a temporary blip.

77.   But Denton was quick to add that a similar meeting held last fall for the shareholders of the oil refiner Ashland Inc. led to big changes at that company.

78.   But changes at Boeing took longer than it had hoped, while the industry recovered faster than it expected.

79.   But critics contend that the changes at Giffen have been largely cosmetic, and that the city could never afford to repeat them at other struggling schools.

80.   But cyclists also say they have seen an alarming change in at titude toward pedal power in recent years.