RAPAPORT... Growth at the retail division of Warren Buffett's Berkshire Hathaway slowed in the third quarter as supply-chain issues led to an inventory shortage.The unit - which includes jewelry chains Borsheims, Helzberg Diamonds and Ben Bridge Jeweler - saw sales increase 5% year on year to $4.8 billion, the company reported Saturday. That represented a gentler rise than the 8% gain the company noted the previous year. Pretax earnings for retail fell 4% to $396 million.The inventory challenges primarily affected sales of cars, which make up the largest portion of Berkshire's retail division."Unit sales continue to be constrained by low new-vehicle production...attributable to the ongoing global computer-chip shortages and other supply-chain disruptions," the company explained.Revenues from manufacturing of consumer products, including jewelry maker Richline Group, slipped 6% to $3.69 billion, while pretax earnings slid 44% to $272 million.Image: A Borsheims store in Nebraska. (Borsheims)