For those just coming into this thread for the first time and considering if you'd like to contribute... In order to get editing access to Google Sheets (which is where this sheet is hosted), you'll need to have an active Google account to do so. There's no cost to create it if you don't already have one, and you can have more than a single Google account if you want to separate what you use them for. The signup page is here: accounts.google.com/signup/v2/webcreateaccount?flowName=GlifWebSignIn&flowEntry=SignUp
These accounts are optionally tied to a 'gmail.com' email address too, so if you already have one of those, it's easy to link them together... otherwise, you'd select the "Use my current email address instead..." option at signup.
There are other options beyond Google Sheets to do this, but it appears that all would require some type of account setup to participate as a group, but using Google should offer better general security than other lesser-known providers.