public int computeNextAge(int currentAge){
	if (currentAge < -100){
	    return currentAge + 100;
	} else if (currentAge == -100){
	    return -1;
	} else if (currentAge == -1){
	    return 1;
	} else if (currentAge == 1){
	    return 50;
	} else if (currentAge < 1750){
	    return currentAge + 50;
	} else if (currentAge < 1900){
	    return currentAge + 25;
	} else if (currentAge < 1970){
	    return currentAge + 5;
	}
	return currentAge + 1;
    }