Ratio of principle and intrest amount of home loan

if i have taken 5 lacs home loan in 2005 at intrest rate of 11% (floating). first emi(aprx) Rs.5,000/- (pncpl 100 and intrst 4900), after the year ratio chang to (pncpl 500 and intrst 4500) and principle part going high and intrest part going down. after two years my paid emi Rs,1,20,000/- at ratio (pncpl 1000 and intrst 4000) Arpox. in that stage bank reduce or increase intrest rate by 0.25%. and revise emi Rs.4500 (aprx) and Ratio is( pncpl 100 and intrst 4400). it means year by year i paying reguraly emi but my principle amt has no reduce. if anybody understand my problem please , reply me and tell me what solution for the same , or having any rules for bank to this proportion ratio.