mutual fund return ? how they calculate the money % ?

if i invest my money in mutual fund
1) 25000rs date of 25-2-2008 & my return is right now -44% means 17532 .
2)if i get some gain in next year %
3) means my actual money is 25000 in 2nd year or 17532. if i keep my money in same fund?
pls. i m confuse about my calculation? give me some good advise… thanks for every one who will give me answer!!!!!!!!

Do I need to reinvest in tax saving bonds (Sec 54) after they mature or can I invest anywhere I want?

Based on your answers I understand that if I invest the long term capital gains amount after selling house property, I have to pay tax only on the interest received on the long term capital gains tax saving bonds (Sec 54). After the bonds mature is it essential to invest in similar bonds or can I invest in other investment options like shares, mutual funds etc.?