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

int main(void){
int rok, i;
long double suma, splatka;
float urok;
scanf("%Lf %Lf %d %f", &suma,&splatka,&rok,&urok);
while(!(suma == 0 && splatka  == 0 && rok == 0 && urok == 0)){
urok = (urok/12)/100;
rok = rok *12;
for(i = 0; i < rok; i++){
	suma = suma + suma*urok - splatka;
	if (suma < 1){
		break;
}
}
if (suma < 1) printf("YES\n");
else printf("NO\n");
scanf("%Lf %Lf %d %f", &suma,&splatka,&rok,&urok);
}
return 0;
}