#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <utility>
#include <stack>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <list>

#define FOR(a,b,c) for(int a=b;a<=c;a++) 
#define SIZEOF(a) (sizeof(a)/sizeof(a[0]))
#define FORARR(i,a) for(unsigned i=0; i<SIZEOF(a);i++)
#define FOREACH(a,b) for(_typeof((b).begin()) a=(b).begin(); a!=(b).end();a++)
#define GETI(a) scanf("%d", &a)

const double PRECISION = 0.0000000001;

using namespace std;

int main(void)
{
	int X,Y,N;
	double r;
	
	while (scanf("%d %d %d %lf", &X, &Y, &N, &r) == 4 && (X || Y || N)) {
		long double mrc = 1 + r/12/100;
		long double debt = X;
		long double totalToPay = X * pow(mrc, N*12);
		long double totalPaid;
		
		if (fabs(r) < PRECISION) {
			totalPaid = Y * N * 12;
		}
		else {
			totalPaid = Y * (pow(mrc, N*12-1)-1) / (mrc-1);
		}
		
		if (totalToPay - totalPaid > PRECISION) {
			printf("NO\n");
		}
		else {
			printf("YES\n");
		}

/*		
		FOR(i,1,N*12) {
			debt *= mrc;
			debt -= Y;
			if (debt - PRECISION <= 0) break;
		}
		if (debt - PRECISION <= 0) {
			cout << "YES" << endl;
		}
		else {
			cout << "NO" << endl;
		}
*/
	}

	return 0;
}