The resolution of the board of directors calling an election to decide whether a special assessment shall be levied, in addition to all other matters required by this division for a resolution calling an election, shall state the amount of the proposed expenditure for which assessment is to be levied, the amount of the assessment which will be levied to raise such amount for expenditure, allowing for a delinquency of 15 per cent, and the rate of the assessment necessary to raise such amount.