There have been a total of 546 data breaches recorded so far in 2014 by the Identity Theft Resource Center (ITRC). Nearly 19 million records have been exposed — and that’s before the breach of an estimated 56 million credit and debit card numbers at Home Depot Inc. (NYSE: HD) is added to the total.

Home Depot’s exposed card total exceeds the 40 million exposed at Target Corp. (NYSE: TGT) in the attack during the 2013 holiday shopping season and the 45.6 million card numbers exposed at TJX Companies Inc. (NYSE: TJX) in a 2007 attack, the largest ever until the Home Depot breach.

When Home Depot announced the total number of compromised records on Thursday, the company said:

The hackers’ method of entry has been closed off, the malware has been eliminated from the company’s systems, and the company has rolled out enhanced encryption of payment data to all U.S. stores. … Home Depot’s new encryption technology, provided by Voltage Security, Inc., has been tested and validated by two independent IT security firms. The encryption project was launched in January 2014. The rollout was completed in all U.S. stores on Saturday, September 13, 2014.

Online security website KrebsOnSecurity noted in its report Thursday that several financial institutions are receiving alerts from card issuers Visa Inc. (NYSE: V) and MasterCard Inc. (NYSE: MA) about cards that “suggest that the thieves were stealing card data from Home Depot’s cash registers up until Sept. 7, 2014, a full five days after news of the breach first broke.

Home Depot’s share price actually rose Thursday, closing up almost 1% at $92.09, in a 52-week range of $73.74 to $93.52. The company’s announcement of the number of cards involved and the approximate dates during which the data was stolen (April through September of this year) appears to put a limit on the damage, and investors like knowing the limits of bad news. However, the report at KrebsOnSecurity may again raise a flag on Home Depot’s reported limits.

The company’s stock traded down about 0.5% in Friday’s premarket session to $91.69.

ALSO READ: The 10 Biggest Data Hacks of All Time

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