Rowland Professional Services (RPS) is a medium-sized accounting practice that has three product segments - Tax, Accounting Services and Insolvency. Currently all overheads for the business are allocated between the three 'product' areas in proportion to sales. Major corporate overheads include executive salaries, human resources (HR), information technology (IT) and general administration. The manager of the Tax Division is currently in dispute with the manager of the Insolvency Division. The Tax Division has had a very good year, with a 50% increase in revenue, whereas Insolvency has not met its revenue target. However it is the Tax Manager that is unhappy with his reported profit. Explain why the Tax Manager may be unhappy with his reported profit in these circumstances, and recommend an appropriate solution for RPS to implement to avoid such disputes in the future