Recession Forecast: A survey by the National Assn. of Business Economists said the economy will slow substantially in 1989 and rising inflation and higher interest rates are likely to topple the country into a recession before the end of 1990. Three out of four of the economists surveyed expected a new recession sometime in the next two years. However, the number predicting a downturn in 1989 dropped to 19% in the latest survey from 40%. The new survey was taken before the latest round of credit-tightening on the part of the Federal Reserve Board.