Explanation: Financial assistance provided by the GoI to support State’s Five-Year Plans is called Central Plan Assistance (CPA) or Central Assistance (CA), which primarily comprises the following:

• Normal Central Assistance (NCA): The distribution of the NCA is formula based (Gadgil-Mukherjee Formula) and is united. The Gadgil Formula of determining the Central Assistance to the State is being adopted from the Fourth Plan and revised subsequently—allocation is made by the Planning Commission.
• Additional Central Assistance (ACA): This is provided for implementation of externally aided projects (EAPs), and for which presently there is no ceiling. Unlike NCA, this is scheme based.
• Special Central Assistance (SCA): This is provided for special projects and programmes, e.g., Western Ghats Development Programme, Border Areas Development Programme, etc. (in exceptional situations, ACA may also be provided). This special plan assistance is given only to Special Category States to bridge the gap between their Planning needs and resources. In other words, SPAs are ACA for the special category states.

Source: Ramesh Singh