PA datasheet -degraded power question?

Dear all SIRs,
when i study PA datasheet, there is a word "degraded power" in all datasheet of linear PA, some part of word as below:

Maximum Output Power
GMSK high power mode(T=25°C) 34.5 35 dBm
GMSK high power mode(degraded power) 32.5 dBm
EDGE high power mode(RMS power, T=25°C) 29 29.5dBm
GMSK medium power mode(T=25°C) 30.5 31dBm
Medium power mode Pmax 29 dBm
Low power mode Pmax 16 17 dBm
Ultra low power mode Pmax 16 17 dBm

what does this word mean?

thanks first

in the other word,
why is only in GMSK high power mode , no occur in medium or low power mode?

It is for showing and guaranteeing performance when some degradation happens. The most probable degradation ahppens in high power mode, as can be expected. One example of source for degradation is oxide breakdowns in gate structures in power transistors.

thanks for your suggestion

Also probably referring to the degraded (lowered) performance with rise in temperature which obviously, will be most noticeable at hi power levels
and higher duty cycle operating modes

Dave