Kemet Corporation (AMEX: KEM) ballooned in price 206.51 percent to start the week, leaping to $13.18 in the first hour of Monday’s trading. Volume was 77,353 shares, compared to a three-month daily average volume of 603,542 shares. Friday, the company filed an application with the state of Delaware for a reverse stock split of the Company’s common stock at a ratio of one-to-three. Kemet, based in Greenville, South Carolina, is a leading manufacturer of tantalum, ceramic, aluminum, film, paper and electrolytic capacitors.

Citigroup Inc. (NYSE: C) slid in price to begin the week, by 0.45 percent in the first hour of Monday’s trading, to $4.45. The banking conglomerate led all volume gainers, however, with128,587,051 shares changing hands, compared to a three-month daily average of 460,630,000. Meanwhile, the Wall Street Journal reported that the Securities and Exchange Commission has subpoenaed a number of former Citigroup brokers, who contend the bank misled investors on risky bond funds.

The Princeton Review, Inc. (NasdaqGM: REVU) plummeted 20 percent in price in Monday’s first hour to $1.24. Volume was 256,776 shares, more than double its three-month daily average. The Framingham, Mass. provider of test preparation, educational support services and online career education services, reported third-quarter revenue increased 59 percent to $54.4 million from$34.3 million in the prior year period. Loss from continuing operations was $8.7 million in the third quarter of 2010, as compared to income of $144,000 in the prior-year period.