National Australia Bank made an unaudited A$1.70 billion statutory net profit for the first trading quarter of its 2018/19 year. Unaudited cash earnings were $1.65 billion.In a trading update yesterday, the bank said cash earnings were up 2 per cent compared to the 2H18 quarterly average, but 3 per cent lower than the comparable quarter last year. Its management commentary highlighted that it was the "only Australian major bank to hold standard variable rates from September 2018 to January 2019, saving around 70 million for over 930,000 loyal customers".The downside to this was that NAB's net interest margin declined, and its revenue suffered.The group's chief financial officer, Gary Lennon, said that compared to the average results of the previous half-year, revenue was "broadly stable with good volume growth offset by lower margins and lower markets and treasury income"."As previously highlighted, customer remediation programs and regulatory compliance investigations are continuing in FY 19 with potential for additional costs, although amounts and timing remain uncertain," Lennon said.In the only positive spin from the Hayne royal commission, NAB's management commentary was that lower than expected expenses for the hearings, a lower marketing spend and "productivity initiatives" contributed to a 3 per cent decrease in this quarter. In terms of asset quality, NAB's credit impairment charges fell by 5 per cent to $193 million, The ratio of 90-plus days past due and gross impaired assets to loans and acceptance is broadly stable at 0.72 per cent.Payment of NAB's final dividend pushed its group common equity tier 1 ratio down from 10.2 per cent at the end of the September 2018 quarter to 10.0 per cent at the end of December 2019. NAB executives also took the opportunity to update the market on exit of its MLC wealth management business. They said "internal separation is progressing well to give MLC management increased autonomy … [however] the current regulatory and operating environment for wealth businesses remains challenging and delay of the intended public markets exit of MLC to FY 20 is now likely."The flat trading update coincided with other negative news from NAB - the announcement that its chief executive officer and chairman were to exit the company in the near future.