By John S. McClenahen Although their economic optimism could be tempered in coming months, senior executives at large U.S. companies plan to boost hiring and investments during the next 12 months, says PricewaterhouseCoopers. A survey of 163 CFOs and managing directors of U.S.-based multinationals conducted from April through June shows 56% plan net additions to their workforces (up from 35% during the second quarter of 2003) and 55% are planning major new investments (up from 41%). The survey also shows nearly 60% of the executives reporting an increase in international sales and 51% reporting an increase in gross margins. However, there are signs of cost-push inflation. Some 41% of the executives reported paying more for what their companies buy, and 37% had increased their own prices.