Inline element
"represents a scalar measurement within a known range, or a fractional value; for example disk usage, the relevance of a query result, or the fraction of a voting population to have selected a particular candidate."
Six floating point attributes:
value (text content can stand in for this)
min
low
high
max
optimum
<meter min="0" max="489972528" value="297786952">297786952 blocks used of 489972528, 192185576 available</meter>