During the 2nd World War in 1940 the government introduced a levy on all "luxury goods" and the phonographic record was included. This became a purchase tax when it came into force, starting at a rate of 33%. This was added onto the wholesale price which, obviously, was passed on to the consumer via the retail price.
So from October 1940, Columbia EMI, and other record companies, used a 2-letter purchase tax code on their records to indicate the tax rate - although every time the government changed the percentage rate then the tax code on the record had to change.
For the period covered by Adge releasing his records the tax code was 'KT' (which had been introduced in July 1963) and then 'JT' (introduced November 23rd 1968) which saw a tax rate increase from 50% to 55%. The actual tax rate then dropped gradually over the years until it was replaced on April 1st 1973 by the current system of 'VAT' which started at 10%. In the early days the tax code was indicated by a sticker placed on the record sleeve but this was stopped in 1963 and the code had to embossed onto the vinyl of the record on one side of the disc - as indicated on the image to the right - a capital K and T either side of the spindle hole. From January 1st 1969 this practice was stopped as no longer required.
Also, in some instances, three letters can be seen stamped around the spindle hole on one side of the record This was because at the actual changeover period of a revised tax rate it was not effective to discard the recent pressing plates (stampers), so the first letter of the tax code was added (as 'T' had always been used as the second letter): During the period we are concerned about the letter 'J' was employed for only a short period following the end of the ‘K’ duration (November 23rd 1968) and so it is possible to find ‘JKT’ slugs on some of EMI’s November/ December 1968 issues and a few 1969 pressings. The purpose of adding the new letter immediately was so that retailers who returned unsold stock of records to the wholesaler would be credited with the same amount of tax that was paid for said records!
For 7" singles Columbia EMI also embossed the tax code on the area of vinyl after the run-off grooves - as can be seen faintly in this image - and this continued after the end of 1968 until the VAT system was introduced in 1973. In some instances there are no tax codes embossed around the spindle hole, and in these cases the codes can be found stamped on the run off grooves.
Records manufactured for 'Export' (i.e. pressed in England but not intended for sale within the United Kingdom) did not require a Tax Code. Thus, in this instance, it is of interest to find examples that include this. More so is to own any UK Export issues that have the label's contradictory statement "SOLD IN THE U.K. SUBJECT TO RESALE PRICE CONDITIONS SEE PRICE LISTS"