I have difficulty with the question for two reasons.

(a) "the crusades" constitute nine official, and numerous unofficial, movements over the course of two hundred years. The demographic composition of the individual crusades varied massively, so it's difficult or impossible to generalize demography across them.

(b) the conception of nationality in the period wouldn't necessarily map to the conception of nationality today. When discussing 'French', for example, there's a huge difference between Norman French, say, and Provencal French. So any breakdown you would get would not map with any reasonable certainty to modern conceptions of nations.

I assume here you're asking only about the crusades to the Holy Land, in which case the simple answer is that it varied over the period, but the great majority were French or German, more so the latter than the former. The First Crusade was primarily a French affair (the catchall Arabic term for the crusaders from then on was al-Franj, or the Franks), the Second was roughly split between the two, and German numbers increased from there- there was actually a smaller Crusade in between the Third and Fourth, known as the German Crusade, which was launched by Henry VI and solely conducted by men from the HRE.

Of course, if you want to get into interesting questions of identity, many of the French crusaders came from lands under the control of the English kings, who were in fact Normans who had recently conquered the island. The most famous English crusader, Richard the Lionheart, spoke no English (his native tongue was Occitan) and spent little time in his kingdom. So whether you would count these crusaders as French or English or Norman or Occitan depends in large part on inadequate modern projections of national identity.