For stock A:
avg(2200,1800)2400−1200=20001200=53
For stock B:
avg(2000,1700)2000−1400=1850600=18560
For stock C:
avg(800,1200)1400−800=1000600=53
For stock D:
avg(500,1000)1200−300=750900=56
For stock E:
avg(1300,1100)1400−1100=1200300=41
For stock F:
avg(1800,1600)2000−1200=1700800=178
For stock G:
avg(1200,1700)1900−1000=1450900=14590
So, stocks A, C, D, and G have SPV >0.5.
Hence, the answer is 4.