Yes. If i am correct and I may not be the wallet has about 100 addresses in it. So even if you grab another address it will still be backed up. But heres the thing im gonna go into some detail.

TLDR: No you dont need to make back up after every depesit to the SAME address.

For example. If you get an address from your wallet and use that for deposits then you just need to back up one time. Your transaction data isn't really stored in the wallet. The wallet holds the keys to the coins on the blockchain. So you never need to backup a wallet for every deposit.

Now I can not stress enough how important the SAME ADDRESS thing is. If you only ever deposit to one address and you made a backup of that wallet then you are golden. I suggest that you make a backup every single time you get a new address to receive inputs. Yes the coins will be there. Basically as far as I know every single coin is like this. Your wallet holds a set of keys which give them access to the funds assigned to them. No one else can do anything to funds assigned to your keys. Also again I know from experience DO NOT forget your wallet password. I know going full paranoid mode sounds good but don't be like my friend that has 90 bitcoins in a wallet he can't use because he forgot the password. So here is what I suggest. Backup your wallet to multiple places that are secure. You can even extract your privake keys directly and store those as well. Just make sure you don't loose that wallet. Many people will claim that using online storage is unsafe. Well yes thats true but crossing the street is also unsafe. So make sure you don't loose your wallet. and make sure your password isn't weak sauce.

While I was writing this two people made great post. Yes just all of that and this. Just don't misplace your wallet, keep multiple backups and if you really want to be as safe as possible get the private keys and write them down. GL