<img src='https://steemitimages.com/p/2BCfkBRHmbhyfuMqxU5YT6Gz2LKYdwfERSsBAXYMrb3W1u9HqYctkN'>

I've started to dig into the Gridcoin Research wallet once again, looking at the new features we've gotten since last. One of these are the change to CBR, constant block reward.

### Constant Block Reward (CBR) in short
When a user has their wallet online and synced to the network, it will try to find the next block. As Gridcoin is a Proof-of-Stake wallet, depending on how large your wallets balance (stake) is, your chance to find one will be larger.

With CBR, anyone finding a new block is rewarded a fixed 10 GRC reward. 

### Annual Percentage Rate (APR) in short
Previous practice was to reward 1.5% APR on the wallets balance that was accumulated between stakes.

As the reward was accumulated between stakes, even when the wallet was offline, a larger holder could come online very few weeks and just claim their accumulated APR in a few blocks and then go offline again. 

Without going into details, this by itself created some issues on the network. When a user staked many blocks in a row, a double spend attack could be a high possibility. They where also not contributing to the network between these sessions. 

Any coin need large investors, nothing bad about that. They should feel they are a part of the network just as any other user. Though, these issues made the reward skew towards the new investors. 

## Going forward with CBR and why it's working for the little guys

Constant Block Rewards are quite complex, and the probability to stake a block is based on a few different factors.

1. Your wallet balance
2. How many unspent transactions your wallet has (UTXOs)
3. The amount of coins trying to stake (the difficulty)

We can guestimate the possibility for a wallet to stake based on the following formula.

`ETTS_with_cooldown = ((2/3) / u) + (16000/b) * d`

Where `u` is number of UTXOs, `b` is wallet balance and `d` is current difficulty.

There are more variables, as a UTXO can't be to small, then it will not stake. 

### Example

Lets say we have a wallet with 36 UTXOs, then we can make a graph of the reward per day depending on Difficulty and Wallet balance. As no rewards are accumulated, the wallet will have to run 24/7 to follow the patern in the following example.

The following graph visualize that a wallet below 3 million GRC will have a better reward output at the large difficulty level of 11, than the now removed APR. Any lower difficulty will result in even better yield.

Daily GRC for CBR is calculated as: `10/(((2/3)/36)+(16000/balance)*difficulty)`
Daily GRC for APR is calculated as: `(balance*0,015)/365`


<center>
<a href='https://cdn.steemitimages.com/DQmThh67Fa2ac6zNN6voxWiKQwsW3Y2Ai4JjYdCyqhzotgD/image.png'><img src='https://cdn.steemitimages.com/DQmThh67Fa2ac6zNN6voxWiKQwsW3Y2Ai4JjYdCyqhzotgD/image.png'></a>
</center>
###### <center>Click to Enlarge</center>

#### Lets take a closer look at wallets below 3 million

<center>
<a href='https://cdn.steemitimages.com/DQmXsV1r2HaBzURVXAqeHVCZymomG4DXUCYvndWveVccY5h/image.png'><img src='https://cdn.steemitimages.com/DQmXsV1r2HaBzURVXAqeHVCZymomG4DXUCYvndWveVccY5h/image.png'></a>
</center>
###### <center>Click to Enlarge</center>

**Conclusion:** New users with low wallet values will receive LARGER rewards with CBR than APR!

A very deep article about Constant Block Rewards are one by @jringo, that can be found at https://steemit.com/gridcoin/@jringo/constant-block-reward-cbr-value-proposal-and-poll 

# <center>Rewards for Science</center>

<div class='pull-right'><a href='boinc.berkeley.edu/
'><img src='https://upload.wikimedia.org/wikipedia/commons/thumb/7/72/BOINC_logo_July_2007.svg/200px-BOINC_logo_July_2007.svg.png'></a></div>

This post was just to demonstrate the new block reward mechanism for Gridcoin, but the network is so much more than just blocks and chains. Gridcoin is a network that rewards users running BOINC, a platform for high-throughput computing on a large scale. 

By running BOINC with any of the whitelisted projects listed on [Gridcoinstats](https://gridcoinstats.eu/project
), you can receive GRC for your contribution to many different types of open scientific research!

### <center>Read more about Gridcoin Research on [Gridcoin.us](https://Gridcoin.us)</center>