Data vs. Value in stat cards

[JasminePParekh]

In the system monitoring tutorial, the value of a stat card is updated with a data parameter. I noticed that we can also directly update the value. Is there a reason to use the data parameter?

With data parameter:

page = site['/monitor']

cpu_card = page.add('cpu_stats', ui.small_series_stat_card(
    box='1 1 1 1',
    title='CPU',
    value='={{usage}}%',
    data=dict(usage=0.0),
    plot_data=data('tick usage', -15),
    plot_category='tick',
    plot_value='usage',
    plot_zero_value=0,
    plot_color='$red',
))

tick = 0
while True:
    tick += 1

    cpu_usage = psutil.cpu_percent(interval=1)
    cpu_card.data.usage = cpu_usage
    cpu_card.plot_data[-1] = [tick, cpu_usage]

    page.save()
    time.sleep(1)

without data parameter:

page = site['/monitor']

cpu_card = page.add('cpu_stats', ui.small_series_stat_card(
    box='1 1 1 1',
    title='CPU',
    value='',
    plot_data=data('tick usage', -15),
    plot_category='tick',
    plot_value='usage',
    plot_zero_value=0,
    plot_color='$red',
))

tick = 0
while True:
    tick += 1

    cpu_usage = psutil.cpu_percent(interval=1)
    cpu_card.value = f"{cpu_usage}%"
    cpu_card.plot_data[-1] = [tick, cpu_usage]

    page.save()
    time.sleep(1)