This VCM represents the ETH token's role as a token for blockspace purchases (the are necessary for any ecosystem-wise asset transfer or state update) and the deflationary appreciation due to fee burning.
Burnt fees originate from the base fees of each transaction included in a block; they are block-local and determined by historical block sizes (a size of a block is the volume of gas expended therein) and the target size. Each time a block exceeds the target size, the base fee is incremented by 12.5%.