(Sharecast News) - Property developer Segro told shareholders on Wednesday that the business "continued to perform well" during the first quarter.The company secured £21m of new headline rent, down from £27.3m in the year ago period, alongside rent roll growth of £6.0m on existing space - thanks to the re-gearing of a number of leases in its Heathrow portfolio, which management labelled as "particularly strong".Segro also secured new pre-lets, worth £11.1m, which while less than the £23.3m observed over the first three months of 2018 was well above the three-year quarterly average of £7.0m, the company said in a statement.A total of 44 projects under construction were expected to generate £57m of annualised rent and were aleady 72% leased, versus Segro's record 73% of pre-letting reached in fiscal year 2018.There were 1.0m square metres of space under development or approved for development a 31 March, up from 0.8m as of 31 December.During the quarter, 100,000 square metres of developments were completed, which were capable of generating £3.8m of headline rent when fully let, with 75% of that space having already been let.The developer's vacancy rent meanwhile decreased from 5.2% as of year-end 2018 to 4.4%, on the back of "strong" lettings of existing and recently-completed speculative space, together with the imapct of disposals and low take-backs.During the quarter, Segro carried out £40.0m of net investments, split between £100m of development capex and land purchases, £10m of asset acquisitions and £70m of asset and land disposals.Following an equity placing in February, net debt declined from £2.7bn at the end of the fourth quarter of 2018 to £2.2bn.