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

int main(void){
  int monthly_pay, years, total_months, debt, i;
  float init_r;
  double r_sum, 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_sum = 1;
    for(i = 1; i < total_months; i++){
      r_sum = r_sum * r + 1;
    }
    if((debt * pow(r, total_months)) < monthly_pay * r_sum){
      printf("YES\n");
    } else {
      printf("NO\n");
    }
  }
  return 0;
}