Programming help newb counter

How do you decrement by specific value.. Im trying to decrement it by 50 for every 1 second... I got the counter to count down by 1 second and now I only need to subtract it by 50 to get the value I need when button is pressed.

#include <LiquidCrystal.h>

LiquidCrystal lcd(12,11,6,5,4,3);
// this constant won't change:
const int  buttonPin = 2;    // the pin that the pushbutton is attached to

// the pin that the LED is attached to

// Variables will change:
int buttonPushCounter = 0;   // counter for the number of button presses
int buttonState = 0;         // current state of the button
int lastButtonState = 0;     // previous state of the button
int value =0;  //Set value for subracted buttonstate



void setup() {
  // initialize the button pin as a input:
  pinMode(buttonPin, INPUT);
  // initialize the LED as an output:

  
  // initialize serial communication:
  Serial.begin(9600);
}


void loop() {
  // read the pushbutton input pin:
  buttonState = digitalRead(buttonPin);

  // compare the buttonState to its previous state
  
    if (buttonState == HIGH) {
      buttonPushCounter  ++;
      value=10000 - buttonPushCounter;
      delay(1000);
      Serial.println(value);
      
      
      lcd.setCursor(7,1);
      lcd.print(value);
      if (value<1){
     lcd.setCursor(0,1);   
     lcd.print("RELOAD");
        delay (100);
        exit(0);
       
      }
  }
  // save the current state as the last state, for next time through the loop
  lastButtonState = buttonState;
 

}