I ran the numbers on KBB.com on more or less the car from above - you can see the difference markedly. This is the 'private sale' price in 'good' condition, about 3 years after the (2015) car came out.
This is for a Accord LX 4 Door Sedan with 33k miles (average 2015 miles).
Over $1600 difference 2015 vs 2014. 2013 has another $1000 off and 2012 another $1500.
Just to show a different car, here's a Subaru Forester, 35k miles (average 2015 miles), base model, "Good", private party. (This model would've been around $22k new., very similar to Accord pricing - new 2017 models are almost identicla in price between the two.)
That holds up a bit better, but still is losing close to $1k per model year for the same mileage. The Forester is one of the best "holds its value" brands for the 2010-2015 period, hence the slower decline, but you can still see a marked decline.