In 2006-07, 23,700 homes were completed compared with 26,000 the previous year and 26,400 in 2004-05. The findings prompted communities minister Stewart Maxwell to stress the need for radical reform.
The minister, who chairs the housing supply task force, said the statistics highlight the ongoing challenge to improve supply and deal with the failure of the Scottish housing system to meet the population's needs.
The government described the rate of building as "simply inadequate". It has set a target for 35,000 completions a year by the middle of the next decade in a bid to tackle a projected shortfall.
"Improving supply to this level is both achievable and necessary if we are to reverse declining affordability," Maxwell insisted.
Housing industry body Homes for Scotland blamed bureaucracy for holding back development in many areas at a time of high demand.
Chief executive Jonathan Fair said: "Although properties are still being bought off the drawing board and people are queuing for homes, other factors such as lack of an adequate land supply, the inefficiencies of the planning system and infrastructure problems are constraining the market."
However, ministers welcomed an increase in the level of new-build starts to 28,000 last year.
Housing Statistics for Scotland is available at PlanningResource.co.uk/doc.