What caused PAYX's expense fluctuations recently?

Paychex Inc (PAYX) recently reported a 5% increase in total revenue for the third quarter, with a 6% growth excluding the impact of the discontinued ERTC program. Despite this positive revenue trend, the company's expenses have fluctuated, with total expenses increasing by 1% to $801 million. The fluctuating expenses can be attributed to several factors:

1. Acquisition-Related Costs: The pending acquisition of Paycor is expected to increase expenses, as the company prepares for the integration of the acquired business. This strategic move is likely to enhance Paychex's market position and expand its suite of HR technology solutions.
2. Interest on Funds Held for Clients: There has been a decrease of 2% in interest on funds held for clients, amounting to $42.9 million. This reduction could be due to lower average interest rates, which is a factor that can influence the interest income earned on cash and cash equivalents held on behalf of clients.
3. Enrollment Decrease in Specialty Plan: The enrollment in the specialty Florida at-risk medical plan has decreased year-over-year, affecting pass-through revenue. This decline might reflect changes in customer preferences or market dynamics, which can impact the revenue generated from certain services.

In summary, the fluctuations in Paychex's expenses are primarily due to acquisition-related costs, changes in interest income, and enrollment decrease in specialty plan. These factors are likely to have a significant impact on the company's financial performance, and investors should monitor these trends closely.