Do tax collections go up with GDP growth?

There is a strong correlation—of ~0.7--between nominal GDP and gross tax collection, according to economists at Nomura. A correlation coefficient is generally measured between -1 and 1, with any measure closer to the first meaning weaker correlation and any closer to the second indicating a strong correlation. “Excluding anomalous years, the average buoyancy of direct taxes (the ratio of tax growth over nominal GDP growth) has been around 1.4-1.6, with that of indirect taxes below 1.0. In FY24, we expect the government to assume tax buoyancies of 1.2 and 1.0 for direct and indirect taxes, respectively,” stated their budget preview note.