Sorry when 60% of funds lost during revolutionary rule (6)
I believe the answer is:
rueful
'sorry' is the definition.
(synonyms)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for rueful that I've seen before include "Repentant" , "Melancholy" , "Full of regret" , "Regretting" , "Filled with regret" .)