The Result of the Great Escape ( from Wikipedia )

There is a Wikipedia page on this here: https://en.wikipedia.org/wiki/Stalag_Luft_III#The_.22Great_Escape.22

* NOTE - it is very sad that some of the people involved in the Great Escape have only recently passed away.

To summarize: (these numbers to do exactly add up?)
76 total escapees
73 recaptured
50 were executed
17 returned
4 sent to concentration camp.
3 escaped

So, I got it backwards, it was around 2/3 that were shot.

Hitler wanted them to be shot as an example to other prisoners, along with Commandant von Lindeiner, the architect who designed the camp, the camp's security officer and all the guards on duty at the time.

Hermann Göring, Field Marshal Keitel, Major-General Westhoff and Major-General von Graevenitz (head of the department in charge of war prisoners) all argued against the executions as a violation of the Geneva Conventions

Hitler eventually ordered SS head Himmler to execute more than half of the escapees. Himmler passed the selection on to General Arthur Nebe, and 50 were executed.

Roger Bushell, the leader of the escape, was shot by Gestapo official Emil Schulz just outside Saarbrucken, Germany.

Bob Nelson is said to have been spared by the Gestapo because they may have believed he was related to his namesake Admiral Nelson. His friend Dick Churchill was probably spared because of his surname, shared with then British Prime Minister.

17 were returned to Stalag Luft III, and 4 were sent to Sachsenhausen concentration camp, where they managed to tunnel out and escape three months later, although they were recaptured and returned there.

Two were sent to Oflag IV-C Colditz.

There were 3 successful escapees:
Per Bergsland, Norwegian pilot of No. 332 Squadron RAF
Jens Müller, Norwegian pilot of No. 331 Squadron RAF
Bram van der Stok, Dutch pilot of No. 41 Squadron RAF