Classifying everyone who do some sort of engineering as "engineer" is not useful info at all. There are so many different kind of engineering earning very different pay.

For e.g. a experienced mechanical enineer in a factory maybe make 50k annual, a marine shipbuilding enginner could make 100k and a oil&gas exploration engineer can make 300k p.a.

The sad thing for singapore is most people studied engineering disciplines like IT, mechanical, EEE, civil etc. which are somewhat the most lowly paid type of engineers out there.