BCN have released their rankings for 2017. These numbers represent about 50% of all Japanese camera retailers, so the numbers do come from a long sample. These numbers do not reflect sales in the rest of Asia, Europe or North America.


Digital SLR camera
Ranking #1 #2 #3
2018 Canon 61.1% Nikon 34.4% Ricoh Imaging 4.2%)
2017 Canon 63.3% Nikon 31.6% Ricoh Imaging 4.8%
2016 Canon 56.2% Nikon 36.7% Ricoh Imaging 6.7%
2015 Canon 54.7% Nikon 39.1% Ricoh Imaging 4.5%
2014 Canon 49.2% Nikon 42.5% Ricoh Imaging 5.2%
2013 Canon 52.7% Nikon 35.1% Sony 7.1%


Mirrorless cameras:
Ranking #1 #2 #3
2018 Olympus 27.7% Canon 21.3% Sony 20.2%
2017 Olympus 26.8% Canon 18.5% Sony 17.9%
2016 Olympus 34.5% Sony 24.8% Canon 13.6%
2015 Sony 34.3% Olympus 22.3% Panasonic 11.9%
2014 Olympus 28.9% Sony 26.5% Panasonic 14.2%
2013 Olympus 29.8% Panasonic 23.3% Sony 20.1%


Digital compact camera (with integrated lens)
Ranking #1 #2 #3
2018 Canon 27.9% Nikon 25.5% Casio 17.2%
2017 Canon 27.3% Nikon 22.1% Casio 19.3%
2016 Canon 30.5% Nikon 21% Casio 14.8%
2015 Canon 28.7% Nikon 15.3% Casio 15.2%
2014 Canon 20% Nikon 15.5% Sony 15.4%
2013 Canon 17.6% Sony 16.5% Nikon 14.1%


Lenses:
Ranking #1 #2 #3
2018 Canon 21.9% Sigma 16.2% Tamron 13.7%
2017 Canon 24% Sigma 14.3% Nikon 12.5%
2016 Canon 24.1% Nikon 15.2% Sigma 13.5%
2015 Canon 21.2% Nikon 15.2% Sigma 13.3%
2014 Canon 20.2% Nikon 18.9% Sigma 12.6%
2013 Canon 23.3% Nikon 19.6% Tamron 14.5%