Google Apps (or any other cloud app) definitely have their place and many find them useful. But I have to ask...do you need to access this spreadsheet from multiple locations and/or devices? If the answer is no, then IMHO there is really no substitute for saving any file to the local machine where you will be using it instead of the "cloud". There is plenty of free office software available along with free templates to create a checking account. Libre Office is just one suggestion. And if you can't afford to lose such a file, saving a copy (or two) with a different filename/location is a lot easier than losing the only copy of the file. It's probably too late to worry about how it could have happened.

This is like asking "where did I leave my door key?". I don't think there's any way to help from afar.

The good news is that if this spreadsheet was an analysis of a checking account, nothing was really lost except the time spent doing the spreadsheet. The information is still available from the bank, however that's accessed.

An easy way to replicate the spreadsheet analysis would be to download the transactions from the bank's website. Most every bank site has this feature, to download a file of account transactions that can easily read by a spreadsheet program. Easier to move around, reformat and structure transactions already in the spreadsheet than to input each transaction manually. I also agree that using a program like Libre Office is probably a better way to do it.

The more important a file is, the more places a backup/duplicate copy should be kept. For my really important files, I have them in at least 4 physically different places, including a copy in a bank vault. Less important, 3. SD cards and thumb drives are cheap insurance. Free programs can automate the backup task. Good luck.

When you say cloud do you mean Google drive? That seems to be where this app backs up too. Mary

Lea: If you access your Sheets via Google Drive, then look along the left side of the Drive page for "Recent" and click on that. Your file may show up there. My recent file shows files from "Earlier this week", "Earlier this month", and "Earlier this year".