GRE Logical Reading: ETS-GRE逻辑单题ETS - A5BXHW8KD1HAXNZ3K$

In the United States, the financing of industrial research by private industrial firms remained steady as a percentage of sales during the period between 1968 and 1978 (after correcting for inflation). But slowdowns in the growth of industrial productivity also occurred during that period, a fact that refutes the notion that the growth of industrial productivity is directly proportional to the amount invested in industrial research.