Parexel International Corp. ended the year on a down note, taking a $12 million tax adjustment to its bottom line, which combined with slow sales for a 76 percent drop in profits for the three months ended June 30.

The Waltham-based contract research organization reported $6.2 million in net income on $292 million in sales for the quarter, compared to $25 million on $332 million in sales for the same period last year.

For the full year, the company reported a $39 million on profit on $1.2 billion in sales, compared to $65 million on $1.1 billion in sales last year.

Included in the fourth-quarter and year-end results was an accounting adjustment for revenues improperly recognized after the company’s ClinPhone acquisition. The full-year and fourth-quarter impacts of the change resulted in a $17 million reduction in consolidated service revenue and a $12 million decrease in operating income. Parexel bought the U.K.’s ClinPhone for $182 million last August.

Company officials said that besides the accounting correction, Parexel was hit by slower service revenues, which CEO Josef von Rickenbach attributed to “headwinds emanating from the broader economic environment.”

But, he added, the company could see some upswing in the second half of the calendar year. Parexel said it expects to book between $263 million and $268 million in sales during the first quarter and $1.12 billion to $1.15 billion in revenues for the full year.