Total company net premiums in the quarter grew 3.7%. Our growth rate was right in line with our plan. Foreign exchange had approximately a 1% adverse impact on our premium growth rate. For the balance of the year, we expect premium growth to pick up continuously quarter by quarter and average mid to upper single digits in constant dollars, excluding agriculture insurance. Crop premiums, as you know, are impacted by commodity prices, and therefore agriculture will likely be down year-over-year about $250 million. Crop premium volume is concentrated in the second and third quarters.
Returning to the quarter, in North America growth was impacted by our continued action to shed risk-transfer workers’ comp business. Even with the current price increases being achieved in the market, this class runs at combined ratios significantly over 100% and simply doesn’t meet our standards. We’ve been exiting this business for three years and by the end of the year our volume will be negligible. Adjusting for this reduction, our underlying growth in North America was around 3% with retail insurance up 3.5 and our wholesale and specialty business about flat.
For our U.S. retail commercial P&C book, our new business writings grew 20% year-on-year, albeit from a relatively low base. The renewal retention ratio as measured by premium in our U.S. retail was 94% in the quarter, up from 92% prior year; and on a policy count basis, our renewal retention rate is also up two points to 83%. Our increased retention rates are a consequence of some better pricing and the fact that we began more rigorous portfolio management a couple of years ago.
In the quarter, some of the areas where we saw our best growth were property and inland marine, risk management casualty, our U.S. brokerage-generated A&H business, and certain specialty casualty lines such as life sciences and foreign casualty. In addition, ACE Westchester, our E&S business, grew for the second consecutive quarter on the strength of property and inland marine in particular.