The license year for all occupational, business or other licenses shall begin October 1 of each year and shall expire on September 30 of the succeeding year. All such licenses shall be issued by the city treasurer beginning August 1 of each year upon receipt of the appropriate license tax, and such tax shall be due and payable on September 30 of each year. If September 30 falls on a holiday or a weekend, the tax shall be due and payable on or before the first working day following September 30. No license shall be issued for more than one year. For each license obtained by any new business, occupation or agent after April 1 of the following year, 75 percent of the license for one year shall be paid and shall be reduced by an additional 5 percent per month for each month thereafter for businesses, occupations or agents which open or start after April, but before October, unless otherwise provided in this article.