if it's sorted then I can get a value using:
<TABLE style="WIDTH: 112pt; BORDER-COLLAPSE: collapse" cellSpacing=0 cellPadding=0 width=149 border=0 x:str><COLGROUP><COL style="WIDTH: 16pt; mso-width-source: userset; mso-width-alt: 768" width=21><COL style="WIDTH: 48pt" span=2 width=64><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; WIDTH: 16pt; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" width=21 height=17> </TD><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; WIDTH: 48pt; BORDER-BOTTOM: #e9e9e9; BACKGROUND-COLOR: silver" width=64>Ainul</TD><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; WIDTH: 48pt; BORDER-BOTTOM: #e9e9e9; BACKGROUND-COLOR: silver" width=64>B</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>1</TD><TD class=xl23 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Name</TD><TD class=xl23 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Score</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>2</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Rich</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.3">30%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>3</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Bob</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.3">30%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>4</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Terry</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.1">10%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>5</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Ainul</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.03">3%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>6</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Howard</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.03">3%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>7</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Sarah</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.02">2%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>8</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Tim</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.02">2%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>9</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">Karim</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.01">1%</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl22 style="BORDER-RIGHT: #e9e9e9; BORDER-TOP: #e9e9e9; BORDER-LEFT: #e9e9e9; BORDER-BOTTOM: #e9e9e9; HEIGHT: 12.75pt; BACKGROUND-COLOR: silver" align=right height=17 x:num>10</TD><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent">JinWe</TD><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext; BORDER-BOTTOM: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent" align=right x:num="0.01">1%</TD></TR></TBODY></TABLE>
=MATCH(0.8,SUMIF(OFFSET($B$1,1,0,ROW($B$2:$B$10)-ROW($B$2)+1),">0"),1)
This will give the row where the % adds to 80% (or the row immediately below the one where the % exceeds 80% if there is no exact match).
The above needs to be entered with ctrl+Shift+Enter (it is an array formula).
There are probably easier ways (I would definitely use a helper column), but I can't think of how you would reproduce this if the data wasn't sorted.