/*
 *      mortgage.c
 *      
 *      Copyright 2011 Contest Team 19 <cteam019@pc-221-151>
 *      
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *      
 *      This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *      
 *      You should have received a copy of the GNU General Public License
 *      along with this program; if not, write to the Free Software
 *      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 *      MA 02110-1301, USA.
 */


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

int main(int argc, char** argv)
{
	int Y, N, i;
	double r, X;
	
	double EPS = 10E-8;
	
	while (1)
	{
		scanf ("%lf %d %d %lf", &X, &Y, &N, &r);
		
		if (X <= EPS && Y <= EPS && N <= EPS && r <= EPS)
		{
			break;
		}
		
		r = r / 12 / 100; // urok za mesic (v procentech)
		N = N * 12; // roky na mesice
		
		for (i = 0; i < 1; i ++)
		{
			X += (X * r);	
			//printf ("X po zuroceni = %lf\n", X);
			
			X -= Y;
			
			//printf ("X = %lf\n", X);
		}
		
		if (X <= 0)
			printf ("YES\n");
		else
			printf ("NO\n");
	}
	
	return 0;
}