ACA calls for tax changes to be 'realistic, manageable and proportionate' for schemes The ACA has called for sensible initiatives to simplify the processes of the pensions tax system. The Association of Consulting Actuaries (ACA) has called for sensible initiatives to simplify the processes of the pensions tax system. In its response to the Office of Tax Simplification's (OTS) January call for evidence on its third-party data reporting review - published today (15 April) - the ACA said the Treasury arm had to make it easier for pension savers to accumulate wealth for retirement. The ACA has long called for a fairer overview of pensions tax on behalf of its adviser member body, who provide advice to the providers of workplace schemes and their sponsors.