DLA Piper's international arm took a £15.5m revenue hit as a result of currency fluctuations in the year to 30 April 2016, its accounts show.

Limited liability partnership (LLP) accounts for the International LLP, which encompasses the firm's business outside the US, state that revenue was negatively impacted by exchange rate changes. Despite this, total turnover for the business edged up marginally to £767.5m, an increase of 0.4% on the preceding year.

Operating profit fell 2.6% to £264.8m from £272m as a result of increased investment, with operating costs climbing by £10.6m to £502.7m.

Staff costs increased to £271.1m of this total, up from from £265.1m in 2015. This came against a slight dip in total staff numbers to 4,916, from 4,926. Fee earner numbers increased slightly to 2,044 from 2,036, while support staff numbers dropped to 2,483 from 2,557.

Senior partner Juan Picon stated in the accounts that the increase in costs was "largely attributable to inflationary pressures on salaries and key investment into delivering effective and efficient client service, for example enhancing the project management capabilities of the services we deliver and the transfer of certain administrative support functions to Warsaw."

DLA opened a services centre in Warsaw in 2015 and cut 200 support staff jobs in the UK as a related part of this move to boost efficiency. Picon also mentioned Africa as a cost during the last financial year, with the firm launching an office in Johannesburg, its first base in South Africa.

DLA International CFO Paul Edwards said the three-year efficiency drive, which is slated to finish during the current financial year, had cost the firm roughly £5m a year.

Edwards added that revenue last year had also been impacted slightly by the firm's demerger with its Turkish and Norwegian operations in 2014 and 2015, respectively.

Yuksel Karkin Kucuk, DLA's former Turkish arm, was shut down by Turkish police in the aftermath of an attempted coup last year, while its Norwegian operation is still connected to the firm and last year entered a verein with firms in Sweden and Finland affiliated with DLA Piper.

The accounts also highlight a significant reduction in total borrowings during the period, with bank loans and overdrafts shrinking from £33.9m to £17.9m.

Key management personnel received £34.2m in the 2015-16 financial year, up from £32m the preceding year.

The accounts show that the number of equity members fell from 676 to 647, a 4.45% drop.

Edwards said: "Without any doubt, we have managed our equity and we continue to manage our equity. Over the last couple of years we have had some slight movement down, next year you will see it go back up again because we are investing in certain areas again."