text: function parse_Cache(data/*:string*/)/*:[Array<number|string>, string, ?string]*/ {
  	var col/*:Array<number|string>*/ = [];
  	var num = data.match(/^<c:numCache>/);
  	var f;
  
  	/* 21.2.2.150 pt CT_NumVal */
  	(data.match(/<c:pt idx="(\d*)">(.*?)<\/c:pt>/mg)||[]).forEach(function(pt) {
  		var q = pt.match(/<c:pt idx="(\d*?)"><c:v>(.*)<\/c:v><\/c:pt>/);
  		if(!q) return;
  		col[+q[1]] = num ? +q[2] : q[2];
  	});
  
  	/* 21.2.2.71 formatCode CT_Xstring */
  	var nf = unescapexml((data.match(/<c:formatCode>([\s\S]*?)<\/c:formatCode>/) || ["","General"])[1]);
  
  	(data.match(/<c:f>(.*?)<\/c:f>/mg)||[]).forEach(function(F) { f = F.replace(/<.*?>/g,""); });
  
  	return [col, nf, f];
  }
  
  /* 21.2 DrawingML - Charts */
  function parse_chart(data/*:?string*/, name/*:string*/, opts, rels, wb, csheet) {
  	var cs/*:Worksheet*/ = ((csheet || {"!type":"chart"})/*:any*/);
  	if(!data) return csheet;
  	/* 21.2.2.27 chart CT_Chart */
  
  	var C = 0, R = 0, col = "A";
  	var refguess = {s: {r:2000000, c:2000000}, e: {r:0, c:0} };
  
  	/* 21.2.2.120 numCache CT_NumData */
  	(data.match(/<c:numCache>[\s\S]*?<\/c:numCache>/gm)||[]).forEach(function(nc) {
  		var cache = parse_Cache(nc);
  		refguess.s.r = refguess.s.c = 0;
  		refguess.e.c = C;
  		col = encode_col(C);
  		cache[0].forEach(function(n,i) {
  			cs[col + encode_row(i)] = {t:'n', v:n, z:cache[1] };
  			R = i;
  		});
  		if(refguess.e.r < R) refguess.e.r = R;
  		++C;
  	});
  	if(C > 0) cs["!ref"] = encode_range(refguess);
  	return cs;
  }
  