Movie clip navigation

I am workin on a project that shows the change in housing density using maps. I have a movie clip “maps” that I have transitioning between various years.

I need to make buttons that go through the movie clip, and when they click it, showing the transformation from that year. I just can’t get the code to work.

Below is what I have:

b1950 is the instance for the button
maps is the instance of movieclip

b1950.onRelease = function () {

if ( maps._currentframe < 10) {
maps.nextFrame;
} else if (maps._currentframe > 10) {
maps.prevFrame;
}
else {
maps.stop();
}

}

Help will be greatfully appreciated,

Thanks