Laffer curve is simplistic in that it assumes a single tax rate and a single labor supply. Actual systems of public finance are more complex, and there is serious doubt about the relevance of considering a single marginal tax rate. In addition, revenue may well be a multivalued function of tax rate; for instance, an increase in tax rate to a certain percentage may not result in the same revenue as a decrease in tax rate to the same percentage (a kind of hysteresis). Furthermore, the Laffer curve does not take explicitly into account the nature of the tax avoidance taking place.
Notional Defined Contributions pension system the pension is based on history of lifetime earnings and is much more heavily influenced by misreporting of one’s income. In Poland NDC pension scheme was introduced in 1996. The country faced serious fiscal challenges with rate of contribution into the pension system having reached 45% of gross wage. The system was implemented in 1999 after long political discussion about its various aspects and was meant as means of both reducing the future pension debt and motivating workers to prolong their careers. Notional Defined Contributions The term Notional Defined Contributions or Non-financial Defined Contributions or NDC refers to