Rank inflation or at established ranks.
In the old days, most if not all of the CO of the battalions in the SAF, are Majors (sometimes only CPT, like commando CPT Gwee Peng Hong, CO 1 SIR, but later he was promoted to Major), and most of the Brigade Commanders were LTC
Nowadays, many COs are LTC
Several years ago, the SAF introduced the SLTC rank, which I believe is to prolong the careers of those LTC who will never be promoted to Colonel, and to entice them to remain for a few more years, and at a higher salary.
Then, there are numerous ranks for senior specialists, such as 3SG, 2SG, 1SG, SSG, MSG, 3Wo, 2WO, 1WO, MWO, SWO and Chief Warrant Officers
In the old days, prior to 1981, there was only SGT, SSG, WO2 and WO1
But the salary is not bad, because the monthly salary for 3WO and CPT is about SGD 5,000