P&N Bank in Western Australia may lay claim to the title of one of the fastest growing banks in Australia."Lending growth in excess of 20 per cent" (and in fact nearer to 21 per cent) was the boast at the top of a media release sent on Friday by the former credit union and now mutual bank.Supercharging the balance sheet has not flowed through to profit, however, for Perth-based P&N Bank.With the full financial report still in production, the bank's confident media release on Friday is the principal source to explain a year of stellar profit growth and a low yield. Only Bank Australia, another mutual and the former bankmecu, has reported faster loan growth over the year to June 2016, on APRA data.Net profit fell eight per cent to A$8.5 million over the year to June 2016. "This was due to the normalising of the effective tax rate to 32 per cent from 21 per cent in 2015 and property asset revaluations," the bank said.Andrew Hadley, P&N's chief executive, pitched the "substantial progress in the realisation of our five year strategic plan" as the explanation for the fast asset growth.The first year of work, Hadley wrote, "was deliberately focused inward on our systems, processes and our people." Hadley said that, from October 2015, P&N "reviewed and delivered an improved member value proposition ... under a platform called "The Power of &."   "Within the first six months of launching this platform, we saw an upswing inmember growth, retention, lending and deposit balances," Hadley wrote.One pillar of this grammatically challenged marketing to P&N's target market is finely priced home loan interest rates. The mutual's most keenly priced home loan, at 3.89 per cent (both the headline and comparison rate) is more than 70 basis points less than the cheapest rate promoted by major banks, though in line with many peers.P&N has an engaged customer base, often ranked near the top of Roy Morgan Research customer satisfaction surveys. This sentiment is reflected in what Hadley assured was "an outstanding net promoter score, some 30 points above industry average."The bank's capital adequacy level decreased 1.48 percentage points to 14.55 per cent.