Dependence of the Forward-Backward (FB) charged-particle multiplicity correlations on position and width of separate rapidity windows is investigated in proton-proton (non-single diffractive) collisions at √ s=0.9, 2.76 and 7 TeV with ALICE at the LHC. Two pseudorapidity intervals (the "forward"and the "backward" windows) of the variable width from 0.2 to 0.8 rapidity units were chosen. Strong and non-trivial dependence of the multiplicity correlation coefficient, obtained for the normalized observables, on the width of the pseudorapidity windows is reported. In addition, we observe an increase of the multiplicity correlation strength with the collision energy. Results are discussed and compared to PYTHIA simulations.