Complex sentence: By the early 1970s, CN was facing increased scrutiny from federal politicians who complained about the railway's continuous losses, mostly brought about by the government forcing the company to undertake various endeavours in the national interest, often at the expense of business and economic logic.
Split into simpler sentences: By the early 1970s, CN faced increased scrutiny from federal politicians complaining about the railway's continuous losses. Successive federal governments of the period had frequently forced the company to undertake various endeavours in the national interest, often at the expense of business and economic logic.