Dynamic text overlay on webcam video

Simple image processing task here. Summary of code below: get video frame from webcam, convert to binary after overlaying a circular mask. Sum 1s and divide by area inside mask to get % of black to white. I'd like to display this number(%) on the video window as it updates with each frame. Currently, the previous value is just overwritten ending up in a mess of numbers on top of each other. Any suggestions? Thank you!

if true
function damagetesting()
%%Reset and initialize
% Pick camera+resolution. Smaller resolution = faster processing
obj = videoinput('winvideo',1,'MJPG_640x480');
obj.FrameGrabInterval=5;
set(obj,'framesperTrigger',1,'TriggerRepeat',Inf);
set(obj,'ReturnedColorSpace','rgb');
im_size=obj.VideoResolution;
[xx,yy]=meshgrid(1:im_size(1),1:im_size(2));
mask=((xx-im_size(1)/2).^2 + (yy-im_size(2)/2).^2  >  (im_size(2)/2)^2);
try
  start(obj);
  hold on;
  figure(1);title(['Center lens on template'])
  h=imshow(zeros(im_size(2),im_size(1)));
  while islogging(obj);              
     im=getsnapshot(obj);
     flushdata(obj);
     im(mask)=0;
     im=im2bw(im,0.6);
     bw=bwlabel(im,8);
     set(h,'Cdata',im);

       imarea=size(im(1)).*size(im(2));
       croparea=sum(mask,1);
       croparea=sum(croparea);
       lensarea=imarea-croparea;
       damagearea=sum(im);
       damagearea=sum(damagearea);
       text(150,150,['damage area ',num2str(damagearea,'%4.2f')],'Color','m');
       stats=regionprops(bw,'BoundingBox','Centroid');
%         for(object=1:length(stats))
%             cent=stats(object).Centroid;
%             plot(cent(1),cent(2),'g+')
%         end        set(h,'Cdata',im);\

    end
catch err
    % This attempts to take care of things when the figure is closed
    stop(obj);
    imaqreset;
    disp('Cleaned up')
    rethrow(err);
end