I am unable to get clarity w.r.t  penal provisons of section 11A of Central excise, S.28 of customs and 73 of Service tax (amended in Finance act 2011) ..

especially regarding that penalty equal to 100% of duty, reduced penalty of 50 % and 25 % at different times..

searching for some summary or tabular (comparitive or some other useful way) method of understanding the provisions... kindly help me...  

thanks in advance

Regards, 

Ashwini.