code: function getSyncProgressPercentage( state, siteId ) {
  	const syncStatus = getSyncStatus( state, siteId ),
  		queued = get( syncStatus, 'queue' ),
  		sent = get( syncStatus, 'sent' ),
  		total = get( syncStatus, 'total' ),
  		queuedMultiplier = 0.1,
  		sentMultiplier = 0.9;
  
  	if ( isPendingSyncStart( state, siteId ) || ! queued || ! sent || ! total ) {
  		return 0;
  	}
  
  	const countQueued = reduce(
  		queued,
  		( sum, value ) => {
  			return ( sum += value );
  		},
  		0
  	);
  
  	const countSent = reduce(
  		sent,
  		( sum, value ) => {
  			return ( sum += value );
  		},
  		0
  	);
  
  	const countTotal = reduce(
  		total,
  		( sum, value ) => {
  			return ( sum += value );
  		},
  		0
  	);
  
  	const percentQueued = ( countQueued / countTotal ) * queuedMultiplier * 100;
  	const percentSent = ( countSent / countTotal ) * sentMultiplier * 100;
  
  	return Math.ceil( percentQueued + percentSent );
  }
docs: Returns a rounded up percentage the amount of sync completed.
  @param  {Object} state    Global state tree
  @param  {Number} siteId   Site ID
  @return {Number}          The percentage of sync completed, expressed as an integer