iOS: I can't get Core Text to use word wrapping. Where am I going wrong?

Question

I've an attributed string with multiple words. I'm trying to draw it along a CGPathRef using Core Text on iOS7. However, even when I set the CTLineBreakMode to kCTLineBreakByWordWrapping, the text does not wrap on words, but on characters. For instance, the red, green, blue and purple pie slices all have enough room to display the string using word wrapping, yet Core Text insists on wrapping on characters in those cases. What am I doing wrong?

    UIFont *font = [UIFont boldSystemFontOfSize:10];

CGContextSetLineWidth(context, 1.0);
CGContextSetStrokeColorWithColor(context, [UIColor clearColor].CGColor);
CGMutablePathRef pathSmaller = CGPathCreateMutable();
CGContextSetFillColorWithColor(context, [UIColor clearColor].CGColor);
CGPathMoveToPoint(pathSmaller, NULL, self.center.x, self.center.y);
CGPathAddArc(pathSmaller, NULL, self.center.x, self.center.y, radius - 5, (beginAngle - 90 - 1) * M_PI / 180, (endAngle - 90 - 1) * M_PI / 180, NO);
CGPathCloseSubpath(pathSmaller);
CGContextAddPath(context, pathSmaller);

CGContextFillPath(context);

CTLineBreakMode lineBreakMode = kCTLineBreakByWordWrapping;
CTParagraphStyleSetting settings[] = {
    { kCTParagraphStyleSpecifierLineBreakMode, sizeof(CTLineBreakMode), &lineBreakMode },
};

CTParagraphStyleRef pstyle = CTParagraphStyleCreate(settings, 1);
NSMutableAttributedString *attrString = [[NSMutableAttributedString alloc] initWithString:@"Mortgage Insurance"];
CFAttributedStringSetAttribute((CFMutableAttributedStringRef)attrString, CFRangeMake(0, [attrString length]), kCTParagraphStyleAttributeName, pstyle);
CFRelease(pstyle);

CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)attrString);
CTFrameRef theFrame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0, [attrString length]), pathSmaller, NULL);
CFRelease(framesetter);

CTFrameDraw(theFrame, context);
CFRelease(theFrame);