The validity of each cryptocurrency's coins is provided by a blockchain. A blockchain is a continuously growing list of records, called blocks, which are linked and secured using cryptography. Each block typically contains a hash pointer as a link to a previous block, a timestamp and transaction data. By design, blockchains are inherently resistant to modification of the data. It is "an open, distributed ledger that can record transactions between two parties efficiently and in a verifiable and permanent way". For use as a distributed ledger, a blockchain is typically managed by a peer-to-peer network collectively adhering to a protocol for validating new blocks. Once recorded, the data in any given block cannot be altered retroactively without the alteration of all subsequent blocks, which requires collusion of the network majority. Overview: Earlier this year, BBVA rebranded itself as BBVA worldwide. Previously, it was called BBVA Compass. While BBVA does have branches Arizona, New Mexico, Florida, Colorado, Alabama, California and Texas. This offer is only available in the other continental states and in Washington, D.C. The 2.15 percent APY on the BBVA money market account is on all balances over $10,000. Looking closer we see that if you can meet the $3,000 minimum investment size, Vanguard’s VMMXX offers an appealing combination of relatively high returns with low expenses. If you don’t have a large amount of cash to invest, you should note that both FMPXX and FIDXX have $1MM investment minimums. If you have less than $1,000, SPRXX doesn’t meet the yield and expense ratio thresholds we laid out, but it doesn’t have an investment minimum.