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

int main()
{
	int borrow = 0;
	int monthly = 0;	
	int years = 0;
	float intRate = 0.0f;
	double result = 0.0; 

	

	while ((scanf("%d %d %d %f", &borrow, &monthly, &years, &intRate)) && (((borrow + monthly + years) != 0)
 		|| intRate != 0)) 			
	{
		int i = 0;
		double monthRate = (((double)intRate / 12.0)/100.0);
		result = borrow;

		for ( i = 0; i < 12 * years; i++ ) 
		{
			result = (result) * (1 + monthRate) - monthly;
			
			if (result <= 0 )	 break;
		} 
		

		// printf("%d %lf", (monthly * years * 12), result);

		//if ( (monthly * years * 12) >= result ) 
		if (result <= 0 )		
		{
			printf("YES\n");
		}
		else
		{
			printf("NO\n");
		}
	}
	return 0;
}