Hello,

I have created a fuel log form using Jotform and airtable base to record the fuel usage which should match the meter reading at the physical fuel tank. There are 2 types of fuel; Diesel and Gasoline. Both are require to record the following details:

• Diesel Tank = This field shows the remaining fuel in the tank. Physically the fuel tank can holds 500 gallons.



• Diesel Start = This field shows the beginning of fuel reading. The start reading should begin with fuel tank 500 gallons = 0.



• Diesel End = This field require the employee to enter the ending of fuel reading after she/him done pumping the fuel into a vehicle/equipment.



• Diesel Total Gallons = This field shows the total gallons that’s has been pumped. (I already got the solution for this field).

My problem in sample use case is — the first employee record the fuel log as following:

• Diesel Tank = 500 (Auto calculate/ formula)



• Diesel Start = 0 (Auto calculate/ formula)



• Diesel End = 30.9
  
  



• Diesel Total Gallons = 30.9 (Auto calculate/ formula)

Then the second or next employee, the fuel log record should be:

• Diesel Tank = 469.1 (Auto calculate/ formula)



• Diesel Start = 30.9 (Auto calculate/ formula)



• Diesel End = 56.3



• Diesel Total Gallons = 25.4 (Auto calculate/ formula)

And it’s continue until the Diesel/Gasoline Tank = 0, then it’s restart again at 500.

What will be the formula for Diesel Tank and Diesel Start? Thank you so much in advanced for the help.