The percentage depletion deduction was conceived in 1932 based on the accepted corporate tax principle that business taxes should be reduced in scale as thevalue of company equipment, structures and other assets diminish over time.
The first industry foresight principle at work here is this: where the same problem applies, a solution that creates value in one industry will turn up to create value in another, even if apparently unrelated.
Liberal Democrat education spokesman Phil Willis said ministers had "abandoned the fundamental principle" of making academic and vocational qualifications of equal value.