Summary: not that good... much less than you expect.
One of the best sources of technical articles on the topic are from Clarkvision.com in my opinion, he supports his statements with math and physics (formulas are provided).
You can start here and read some other articles.
http://www.clarkvision.com/articles/dynamicrange2/
According to him,
This shows that the Canon 1D Mark II has a much higher dynamic range than either Fujichrome Velvia slide film and Kodak Gold 200 print film. Kodak Gold 200, in this test, showed 7 stops of information, Fujichrome Velvia 5 stops, and the Canon 1D Mark II, over 10 stops of information! Further image analysis shows at least 10.6 stops are recorded by the canon 1D Mark II camera (the full range of of detail in this image, Other testing of the noise level versus intensity shows the Canon 1D Mark II has 11.7 stops of dynamic range.
And keep in mind that film has usually more noise than digital.
Compare with a modern dSLR (APS-C) like the Nikon D7100 http://www.dxomark.com/Cameras/Nikon/D7100---Measurements or http://www.sensorgen.info/NikonD7100.html that measures about 13 stops if you look at pixel level (choose "screen" in the graphs from DxO).
Some more articles you may find interesting:
http://www.clarkvision.com/articles/film.vs.digital.1/
http://www.clarkvision.com/articles/film.vs.digital.summary1.html/
https://www.onlandscape.co.uk/2014/12/36-megapixels-vs-6x7-velvia/
Edit: this was about color negative film, as requested. I was looking for data about BW films but I haven't found much. Details are surely better, I'm not sure about dynamic range.
Edit 2: this analysis by Clarkvision compares dynamic range stops of a digital camera with film using specifications by Kodak (that means averaging a 48 micron spot, check the link for more info):
http://clarkvision.com/reviews/how-to-interpret-reviews/
The result is that (section "Derived Sensor Parameters") a Canon 7D Mark II at 100-200 ISO has about 18 film-equivalent stops. Good luck finding a film able to even come close to that...
Edit 3: if you downvote please explain in the comments, don't throw the stone and hide the hand please.