bY = 1971;
bM = 12;
bD = 9;


today = new Date();
Y = today.getFullYear();
M = today.getMonth() +1;
D = today.getDate();

lmY = Y - bY;

if(bM > M){
	lmY = lmY -1;
}
else if((bM == M) && (bD > D)){
	lmY = lmY -1;
}
else {
	lmY = lmY;
}

document.write(lmY);