| Total salary | Mean | T-test | |
2003-2008 | 2009-2014 | |||
U.S | 396.05 | 386.42 | 405.69 | 0.048 |
Japan | 52.65 | 48.99 | 56.32 | 0.055 |
Korea | 33.64 | 30.56 | 36.72 | 0.067 |
Taiwan | 5.28 | 5.01 | 5.56 | 0.092 |