Equity Oil Co., 10 W. 300 South, ended 1990 with net income of $2.1 million, a 36 percent increase over the $1.5 million in 1989, according to Fred H. Evans, president.

Revenue in 1990 reached $19.5 million, a 28 percent increase over the $15.3 million for 1989. Net income for the fourth quarter of 1990 was $1.5 million or 13 cents per share, a 181 percent increase over the $544,569 net income in the same quarter a year ago.Evans said Equity's 1990 net income includes two unusual non-cash charges taken in the second quarter of the year. One was a $1.9 million charge resulting from the abandonment of two wells in Pecos County, Texas, and a $336,000 charge to leasehold abandonments.

He said higher net income and revenue for the fourth quarter and all of 1990 were the result of a dramatic increase in oil prices since early August and an increase in oil and gas production.

The average price of oil during 1990 increased 22 percent to $23.04 per barrel from $18.87 per barrel in 1989.

Oil production in 1990 increased 5 percent to 696,907 barrels compared to 665,237 barrels in the 1989. Gas production increased 32 percent from 1.4 billion cubic feet from 914 million cubic feet in 1989.

Evans said the situation in the Middle East will continue to largely control the price of oil and gas in the foreseeable future and the volatility of the pricing impacts the company's budgeting process.

The company is budgeting exploration activity for 1991 on the basis of the average oil and gas prices realized last year. In 1990 the company spent $7.3 million for exploration and development, which was 76 percent of cash flow from continuing operations.