Vuol dire "dividere il guadagno in fette identiche" e allocare/far entrare nei risultati delle operazioni una fetta ogni periodo. You will find "straight line basis" if you google with "accounting" or "depreciation". Esempio: Qualcuno ti paga oggi in contanti 100,000 euro per i diritti di usare un disegno artistico che hai creato. I diritti durano 5 anni. On a straight line basis, tu porti al conto economico 20,000 al'anno.
I've often heard 'on a straight line basis' referring to depreciation (opposite of 'on a reducing balance basis') but I've never heard it used referring to income.
Without adequate context, it's difficult to make even an educated guess.
A stabilimento balneare could divide its annual income by 12 to obtain some kind of an average 'monthly income'. That would be 'on a straight line basis' -- but it would create a ridiculous suggestion that February's income and August's income were the same amount.
Actually this case refers to a leasing for which "one year grace period or free rent" has been granted.
It depends if we look at the tenant or the landlord position (cost or profit).
Therefore the accounting rule I read wants me to use this straight line basis method in order to take into the account the first free rent period as well