Refer to a trigger condition value within a template action in the same automation

I have this automation that triggers when a value is above 80 (% of the battery level).

When this happens, I increment the number of charges (var.number_of_car_charges) and then subtract the 80% from the delta charge, so that I’ll wait for another 80% of charge before triggering again.

alias: Count complete charges of the car
description: Car has been charged more than 80%
trigger:
  - platform: numeric_state
    entity_id: var.previous_car_batt_delta_charge
    above: "80"
condition: []
action:
  - service: var.set
    data:
      entity_id: var.number_of_car_charges
      value: "{{ (states('var.number_of_car_charges') | int(0)) + 1 }}"
    enabled: true
  - service: var.set
    data:
      entity_id: var.previous_car_batt_delta_charge
      # How to replace the value 80 below with a variable that points to the 'above' value in the trigger?
      value: "{{ (states('var.previous_car_batt_delta_charge') | int(0)) - 80 }}"
    enabled: true
mode: single

This works, but I would like to replace the 80 value in the last template with the same value I’ve written in the trigger. Is that possible?

I mean, something like this.trigger[0].above that allows me to change the hardcoded value in a single place within the same automation.