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

int main(void){
long splatka, rok, i;
double suma, urok;
scanf("%lf %d %d %lf", &suma,&splatka,&rok,&urok);
while(suma && splatka && rok && urok){

for(i = 0; i < (rok*12); i++){
	suma = suma + suma*((urok/12)/100) - splatka;
}
if (suma <= 0) printf("YES\n");
else printf("NO\n");
scanf("%lf %d %d %lf", &suma,&splatka,&rok,&urok);
}
return 0;
}