The main benchmarks closed higher ahead of this week's key inflation update. Stock started the week on a positive note, with the main benchmarks closing higher Monday. Blue chip stocks outperformed thanks to strong gains for drugmaker Amgen (AMGN) and aircraft manufacturer Boeing (BA), while Warren Buffett's Berkshire Hathaway (BRK.B) put in an impressive post-earnings showing. After closing last week in the red, the S&P 500 (+0.9% at 4,518) and the Nasdaq Composite (+0.6% at 13,994) notched sol