'Percentage' was a British special forces operation to parachute one Czechoslovak agent into the Čáslav area of German-occupied Czechoslovakia (3/4 October 1941 onward).

During 1941 the Germans cut the very important radio communication link between occupied Czechoslovakia and London. This communication link had been maintained from the
autumn of 1939 through a series of radio transmitters operated by members of the home front resistance movement, who worked under the codenames 'Sparta I' and 'Sparta II'. The operation of the 'Sparta I' radio was originally controlled by the home front’s political headquarters and then, from the start of 1940, by the civil unit of the Central Home Resistance Command
(ÚVOD). From 8 July 1941 only one radio station, 'Sparta I' operated by the radio group of Professor Krajina, maintained contact with London. This fact could have influenced the success of all subsequently planned actions in Czechoslovakia, including 'Anthropoid', and its needs led to the realisation of 'Percentage'.

During the night of 3/4 October 1941, Lance Corporal Frantisek Pavelka was dropped by parachute near Koudelov in the Čáslav area. Pavelka’s task was to establish contact with the leading representatives of the home front, deliver a message from the movement’s leadership in London and hand over crystals for new radio stations, telegraph keys and a new cypher key. Pavelka was also carrying an example the Mk III radio supplied by the Special Operations Executive, and with this was to help maintain communication between the home front and London.

Although Pavelka landed 22 miles (35 km) from the intended
drop zone near Nasavrky, he was able to establish contact with the domestic home front at the alternative address of Václav Dolezal at Nasavrky on 4 October, and also managed to contact the ÚVOD organisation. However, Pavelka was captured by the Gestapo as early as 25 October, sentenced to death by the People’s Court in Berlin and executed in Plötzensee.