About 3,800 KCR staff are unhappy about a plan to modify their retirement scheme which they say might leave them with reduced returns. A referendum on the scheme will be conducted until Tuesday. If more than 90 per cent of staff agree to switch to the modified scheme, the remaining 10 per cent will need either to join it or choose the Mandatory Provident Fund (MPF) scheme to be operating by the year's end, according to letters distributed by the company last week. Although the percentage of contributions by the company would remain at between 12 per cent and 16 per cent in the modified scheme, staff were unhappy that it would not offer the 'safety net' provided by the existing scheme, staff spokesman Ko Pak-kwun said. Retiring staff now take home a sum from the provident fund based on its investment return. But if the investment return is low, they can opt for a guaranteed amount, calculated according to a complicated formula based on their years of service. But the guarantee of being able to take home whichever was the higher amount would be removed from the new scheme in line with the 'market trend', a company spokeswoman said. Mr Ko said: 'Although there's no cut in contributions, many staff question why the safety net is being scrapped. 'If the market is sluggish when we retire, we will stand to lose out under the modified scheme.' A spokesman for the MPF Scheme Authority, without commenting on individual cases, said companies could modify retirement plans if 90 per cent of staff agreed. The company spokeswoman said if less than 60 per cent of staff voted for the modified scheme, it would be abandoned. If the support rate was between 60 and 90 per cent, the present scheme and the modified scheme would run concurrently, and both would be registered for exemption from the MPF, she said.