Total compensation for Express Scripts Chairman and CEO George Paz slid 17 percent in 2011, matching a drop the pharmacy benefits manager’s stock took largely after it announced a $29.1 billion acquisition of competitor Medco Health Solutions Inc. last July.

Paz, 56, received compensation valued at $8.5 million, according to an Associated Press analysis of the St. Louis company’s annual proxy statement filed with the Securities and Exchange Commission. That compares to a total of $10.3 million in 2010.

The 2011 compensation consisted mostly of stock and option awards adding up to $7.2 million. It also included a $1.1 million salary and $200,211 in other compensation.

Paz and other Express Scripts executives received no bonuses last year after the company’s adjusted earnings fell short of the company’s target. In contrast, he received a $2 million performance-related bonus the previous year.

Paz has served as CEO since 2005 and had as especially busy year in 2011. The company unveiled plans to buy Medco in a cash-stock deal that creates the largest pharmacy benefits manager in the country by far.

Pharmacy benefits managers, or PBMs, run prescription drug plans and use their large purchasing power to negotiate lower drug prices. They make money by reducing costs for health plan sponsors and members. Express Scripts clients include employers, insurers, government agencies and unions.

Paz has said the Medco deal will lower costs and improve patient care, but the deal’s size immediately drew concern from some competitors and members of Congress. However, it passed a Federal Trade Commission review, and the acquisition closed earlier this month.

Express Scripts shares climbed initially to close at $57.30 the day after the companies announced the deal on July 21. But the stock then slid below $36 before rallying to end 2011 at $44.69. Shares have since climbed more than 30 percent to surpass the initial gains they made after the deal announcement.

The PBM also engaged in public spat last year with Walgreen Co., the nation’s largest drugstore operator, over terms of a new contract. Express Scripts had paid Walgreen to fill prescriptions, but their contract ended in December after the companies failed to iron out a deal.

Overall, Express Scripts Holding Co. earnings grew 8 percent last year to $1.28 billion, or $2.53 per share, while revenue rose 3 percent to $46.13 billion.

The Associated Press executive compensation formula is designed to isolate the value the company’s board placed on the executive’s total compensation package during the last fiscal year. It includes salary, bonus, performance-related bonuses, perks, above-market returns on deferred compensation and the estimated value of stock options and awards granted during the year.

The calculations don’t include changes in the present value of pension benefits, making the AP total different in most cases from the total reported by companies to the SEC.

Paz also made about $13.3 million last year from previously awarded stock units that had vested. That total was not included in AP’s calculation of his 2011 compensation.