Why are economies becoming more capital-intensive?

When comparing the net corporate investment rate with real GDP growth or when looking at the net non-housing capital stock in volume terms relative to real GDP, we see that the US and euro-zone economies have become increasingly capital-intensive. This may come as a surprise, because it is conceivable that the shift from industrial capital to technological services capital would, on the contrary, have made the economy less capital-intensive. But, on the one hand, we can see that the slowdown in total factor productivity over time has made it necessary to have both more capital and more labour to achieve the same production. The virtual disappearance of technological progress explains why economies have become more capital-intensive. On the other hand, we can see that the real long-term interest rate has been falling, which has encouraged the use of more capital-intensive technologies .