According to the Purchasing Managers Index, which surveys local businesses, the private sector built on recent improvements by posting record rises in output and new orders in April.It also said employment has continued to increase sharply.Richard Ramsey, Chief Economist NI at Ulster Bank, explained: "Northern Ireland's economic recovery moved up another gear last month according to the latest PMI survey."The latest surge in business activity and new orders growth is primarily due to improvements within the Northern Ireland and UK markets. In turn, this has been linked to growing confidence in the economic outlook and housing markets of these two economies. "Meanwhile, new export orders posted their tenth successive month of growth in April."Mr Ramsey added that while the recovery is picking up speed, it will still take some time before it has caught up with other regions of the UK.He added: "Despite Northern Ireland's outperformance of the UK in the latest survey in some of the key indicators, it should be remembered that Northern Ireland's economic recovery, in terms of both output and employment, has lagged significantly behind that of the UK. "Therefore the local economy still faces a prolonged period of catch-up in the months and years ahead. However, it is encouraging to see that the recovery is gaining momentum."