#include <cstdio>
#include <cstdlib>

#define eps 1e-10

int main(int argc, char** argv)
{
	int X = 0,Y = 0,N = 0;
	double r = 0;
	bool splaceno;
	long double dluh;
	
	while(true){
		scanf("%d %d %d %lf", &X, &Y, &N, &r);
		if ( X == 0 && Y == 0 && N == 0 && r == 0) break;
		splaceno = false;
		
		dluh = (double)X;
		int max = N*12;
		
		for (int i = 0; i < max ; i++) {
			//if (dluh + eps < 0 || dluh - eps < 0)  {
			if (dluh < 0)  {
				splaceno = true;
				break;
			}
			dluh += dluh * ((r/12)*0.01);			
			dluh -= Y;	
		
		}
		
		if (splaceno) printf("YES\n");
		else printf("NO\n");
		
		}
		
		
	return 0;
}