This link below will take you to the DfE website and all the information that you could possibly want:
...or you can read all about it below.
Y6 Results - Progress
Progress scores are ranged from -5(lowest) to +5)highest) with the national average being zero
Reading = +3.2
Writing = -1.6
Maths = +1.2
2016 Performance Tables latest update : (4 Oct 2016)