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

double X, Y, r, p, q ;
int    N, n ;

int main()
{
  while (1)
  {
    scanf("%lf %lf %d %lf\n", &X, &Y, &N, &r) ;

    if (N == 0)
      break ;

    N *= 12 ;

    r /= 100.0 ;

    q = (1 + r / 12.0) ;

    for (n = 1 ; n <= N && X > 10e-8; n++)
    {
      X = X * q - Y ;
    }    

    if (X < 10e-8)
    {
      printf("YES\n") ;
    }
    else
    {
      printf("NO\n") ;
    }
  }    
  return 0 ;
}