#include <stdio.h>
#include <math.h>
#define MONTHS 12

int main(void){
  int monthly_pay, years, total_months, debt;
  double necessary, r, r_m;
  float init_r;
  
  while(1){
    scanf("%d %d %d %f", &debt, &monthly_pay, &years, &init_r);
    if(debt == 0 && monthly_pay == 0 && years == 0 && init_r == 0){
      break;
    }
    total_months = MONTHS * years;
    r = init_r / (MONTHS * 100) + 1;
    if(debt * r - debt > monthly_pay){
      printf("NO\n");
      continue;
    }
    r_m = pow(r, total_months);
    necessary = r_m / (r_m - 1) * (r - 1);
    if(monthly_pay < debt * necessary){
      printf("NO\n");
    } else {
      printf("YES\n");
    }
  }
  return 0;
}