#include <stdio.h>
#include <string.h>

int main()
{
	int Y, N;
	float X, r;

	while(scanf("%f %d %d %f\n", &X, &Y, &N, &r)) {
		if(X == 0 && Y == 0 && N == 0 && r == 0)
			break;
		
		int months = 12*N;
		for(int i = 0; i < months; i++){
			X += X*(r/12/100)-Y;
			//printf("%f %f\n", X, (r/12));			
		}
		

		if(0 >= X)
			printf("YES\n");
		else
			printf("NO\n");
		
	}
	return 0;
}