Our share tips made good headway last week with all four of the investment portfolios recording valuation gains when we carried out our review of progress on Wednesday morning.

The best performance was staged by the 2011 selections which added a remarkable 3%, helped by a surge in support for Royal Mail after it announced plans to streamline collection services.

The 2012 and 2013 portfolios also out-performed the FTSE 100 index with gains of around 2% over the week with STV, Signet, WPP and Halma among those to recover some of the ground lost in previous sessions. Only the latest 2014 selections disappointed to show only a marginal overall increase as progress continued to be held back by the poor showing of foreign currency earners such as IMI, Dialight and Ricardo.

We are convinced these export-led business will stage a bounce once the pound returns to reasonable levels and are encouraged by the US dollar which has risen more than 2.5% against sterling in recent weeks.

But we have already given the shares the benefit of the doubt by lowering their stop-loss levels and will evict any of these companies from the portfolio if they trigger sell signals at the new target prices.

We decided to take a punt on an export-led company on Wednesday when we added Edinburgh-based surveillance specialist IndigoVision to our 2013 portfolio.

Figures due next month will show the impact of the pound's strength earlier this year though annual profits should still show a 17% increase to around £2.4 million, with a near 50% increase in orders from the Asia Pacific region. Followers say profit margins are likely to be held back by the costs of increased employee numbers but this should show in a further boost in the coming months.