It looks like an 80's or at best 90's model. I am leaning towards 90's as it is CDI (if the side panel is original) but still has drum brakes.
A bit of googling says it could be a 2001 though.
Over its lifetime, the CG125 has received numerous enhancements and tweaks:
The electrics were upgraded from 6 V to 12 V (1985 in UK)
The old contact breakers were replaced by electronic ignition (1995 in UK).
An electric start was added in 2001, originally alongside the original kick start and replacing it completely in 2004 (in the European Market).
2004 saw a number of further changes in the European market:
The front drum brake was replaced by a disc brake
A new instrument cluster, including a fuel gauge for the first time, replaced the old square unit.
The fuel capacity was increased from 12 litres (2.6 imp gal; 3.2 US gal) to 13 litres (2.9 imp gal; 3.4 US gal)
The styling was modernised
The chain casing was dropped in favour of a simpler chain guard