JMO, the pay cut for him occurred when he was still at the car dealership, in 2014, when Bella was a baby. I don't know when Shanann left her employment at the hospital, but I believe she was working at the hospital in 2014 and was making around $35,000 a year.
They had a nearly $60,000 drop in income from 2013 to 2014 and by the time Celeste was born in 2015, which was when they declared bankruptcy, he was working at Anadarko, and the total drop in income from 2013 was over $100,000. They were down to around $40,000 in income that year and Shanann was having a difficult pregnancy with CeCe. Shanann's parents were living with them around that time. to help.
At the time of the murders, CW and Shanann's incomes were about the same, per CW. If they were each making $60,000 to $70,000 per year, that's a total income of between $120,000 to $140,000. JMO.