* Specific model: Even within the 1994 Thunderbird model year, there might have been slight variations (coupe vs. convertible, trim level etc.) affecting aerodynamics.
* Testing conditions: The Cd is measured in wind tunnels under specific, controlled conditions. Different testing methods will yield slightly different results.
* Data availability: Comprehensive aerodynamic data for older vehicles isn't always readily available to the public.
While you won't find an exact figure readily published, you can expect the Cd to be in the range typical for similar-sized, relatively aerodynamic cars of that era. A reasonable estimate would likely be between 0.32 and 0.38. This is just an approximation, however.
