Determination of h2o2 using kmno4?

ok, so i have a 100ml bottle of an unknown H2O2 solution which claims to contain 3% H2O2 and i aim to determine whether that 3% is accurate. I conducted a titration experiment in which i added 1ml of the H2O2 solution, 5ml of H2SO4 and 25ml of H2O and titrated it against 0.02M KMnO4. It took 37ml of KMnO4 to reach the equivalence point . But now i do not have a clue how to calculate the percentage of H2O2. Help please?