Before revision:  This work suggests that (1) macro-factors in the Emergent Period  have led to persistent growth in US  approvals enjoyed since 1974, (2) the CHE may be a valued method to explore the constancy of extrinsic pressures on time series data, and (3) adds further evidence that innovation-related economic cycles exist (as supported via the proxy metric of US drug approvals).
After revision:  This work suggests that (1) changes in extrinsic factors (e.g., of economic and/or policy origin ) during the Emergent Period have led to persistent growth in US approvals enjoyed since 1974, (2) the CHE may be a valued method to explore the constancy of extrinsic pressures on time series data, and (3) adds further evidence that innovation-related economic cycles exist (as supported via the proxy metric of US drug approvals).