How To Get Sub Categories of Current Category In Magento 2

<?php 
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
$category = $objectManager->get('Magento\Framework\Registry')->registry('current_category');
$subcats = $category->getChildrenCategories();
$_helper = $this->helper('Magento\Catalog\Helper\Output'); 
?>
<?php foreach ($subcats as $subcat): ?>
 <?php if($subcat->getChildrenCategories()->count() > 0): ?>
               <li class="item">
                    <a href="<?php echo $subcat->getUrl(); ?>">
                        <?php echo $subcat->getName(); ?>       
                        <?php echo $subcat->getChildrenCategories()->count(); ?>
                    </a>
                </li>
  <?php endif; ?>
<?php endforeach; ?>