A bad feeling

Chen Show Mao spent 40 of his 50 years out of Singapore. There is this rumour that he may be disqualified to stand for election under the 10 year residency condition. The public data that I have gathered is that he came to Singapore in 1972, completed his primary, secondary and A level in 1979. This is followed by 2 ½ years of NS. He graduated from Harvard in 1986. From these data, the number is