<?php
/**
 * Created by PhpStorm.
 * User: vovas
 * Date: 12/28/2017
 * Time: 1:43 PM
 */

$data = [
    [
        "id" => 1,
        "users" => 100,
    ], [
        "id" => 2,
        "users" => 108,
    ], [
        "id" => 3,
        "users" => 114,
    ], [
        "id" => 4,
        "users" => 98,
    ], [
        "id" => 5,
        "users" => 105,
    ], [
        "id" => 6,
        "users" => 110,
    ], [
        "id" => 7,
        "users" => 140,
    ], [
        "id" => 8,
        "users" => 141,
    ],
];


function getPercent($prev, $current)
{
    return ($current - $prev) / $prev * 100;
}

function getPrev($data, $currentIndex, $backNumber)
{
    $index = $currentIndex - $backNumber;
    return $index > 0 ? $data[$index] : $data[0];
}

$totalUsers = $data[0]['users'];
foreach ($data as $index => &$item) {
    $item['per_day'] = getPercent($totalUsers, $item['users']);
    $back3Days = getPrev($data, $index, 2);
    $back7Days = getPrev($data, $index, 6);
    $item['per_3_days'] = getPercent($back3Days['users'], $item['users']);
    $item['per_7_days'] = getPercent($back7Days['users'], $item['users']);
    $totalUsers = $item['users'];
}
?>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"
      integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<table class="table">
    <thead>
    <tr>
        <th>#</th>
        <th>Total users</th>
        <th>Per day</th>
        <th>Per 3 days</th>
        <th>Per 7 days</th>
    </tr>
    </thead>
    <tbody>
    <?php foreach ($data as $d) { ?>
        <?php
        $perDay = round($d['per_day'], 2);
        $per3Days = round($d['per_3_days'], 2);
        $per7Days = round($d['per_7_days'], 2);
        ?>
        <tr>
            <th scope="row"><?= $d['id'] ?></th>
            <td><?= $d['users'] ?></td>
            <td class="<?= $perDay > 0 ? 'success' : 'danger' ?>"><?= $perDay ?> %</td>
            <td class="<?= $per3Days > 0 ? 'success' : 'danger' ?>"><?= $per3Days ?> %</td>
            <td class="<?= $per7Days > 0 ? 'success' : 'danger' ?>"><?= $per7Days ?> %</td>

        </tr>
    <?php } ?>
    </tbody>
</table>