Revenue growth is an elusive commodity in the financial services industry at the moment, but Westpac is betting it can boost revenue by getting more of its banking customers to buy products in fast-growing wealth management sectors.Brad Cooper, the head of BT Financial Group, Westpac's wealth management division, briefed investors yesterday on the group's strategy in this area.Westpac claims the highest wealth cross-sell among the big banks. It rates its penetration at 20.3 per cent, based on a Roy Morgan survey of the number of customers with a deposit or transaction account, mortgage, personal loan or credit card who also have a managed investment, superannuation account or insurance policy.Among its high net worth customer base, 26 per cent have a wealth product.Its peers have penetration rates of 13.6 to 18.4 per cent.St George has a penetration rate of 14 per cent, but has the fastest rate of growth, according to the Roy Morgan survey. The group average is 17.7 per cent.Cooper said the two key areas in wealth management were superannuation and life insurance. He expects the overall superannuation market to achieve compound annual growth in earnings of 7.4 per cent to 2017. And he expects the life insurance sector to achieve compound annual growth of 7.3 per cent over the same period.Cooper said BT was shifting its focus to the more profitable segments in the wealth management market: affluent customers aged over 45, who are big depositors and make the biggest contributions to superannuation and are also keen buyers of life insurance; and small business, which represents a big deposit base. "Prime of life" customers (people aged 45 to 65) account for 80 per cent of wealth industry inflows. Cooper said this group was under-represented in BT's customer base.As well as working on higher levels of cross-sell to Westpac and St George customers, BT has started distributing through an independent financial adviser this year.