asked the Chancellor of the Exchequer what the gain to therevenue would be if incomes, whether earned or unearned, were taxed at 100 per cent. above (a) £15,000, (b) £16,000, (c) £17,000, (d) £18,000, (e) £19,000, (f) £20,000, (g) £21,000, (h) £22,000, (i) £23,000, (j) £24,000, and (k) £25,000.

The readily available information relates to taxable incomes, rather than to gross incomes.Estimates for a full year at 1979–80 income levels are as follows:

Taxable Income above					Yield
£					£ million
15,000	…	…	…	…	770
16,000	…	…	…	…	670
17,000	…	…	…	…	590
18,000	…	…	…	…	520
19,000	…	…	…	…	460
20,000	…	…	…	…	410
21,000	…	…	…	…	370
22,000	…	…	…	…	330
23,000	…	…	…	…	300
24,000	…	…	…	…	270
25,000	…	…	…	…	250

The rate of 100 per cent. above the levels of taxable income quoted has been substituted for the effective marginal rates of tax, including investment income surcharge where appropriate, which are charged in 1979–80. In the reply to my hon. Friend the Member for Eastleigh (Mr. Price) on 6 December 1979—[Vol. 975, c. 337]—the rate of 100 per cent. was substituted for the nominal marginal rate in 1979–80 excluding any investment income surcharge payable.