Calculate gross and net transaction volume on a connected account

connect_account_volume.rb

require 'stripe'

Stripe.api_key = "YOUR-API-KEY"

# Authenticate as the connected account and retrieve the first 100 transactions
transactions = Stripe::BalanceTransaction.list({limit: 100},{stripe_account: "acct_YourConnectedAcctID"})
total_volume = 0
net_volume = 0

# Iterate through transactions using auto-pagination
transactions.auto_paging_each do |txn|
  # Sum the total payments volume
  if txn.type.eql?('charge')
    total_volume += txn.amount
  end
  # Sum the net transaction volume
  net_volume += txn.amount
end

puts "Total volume: #{total_volume}"
puts "Net volume: #{net_volume}"

Thank you for this gist. However, I'm not getting the correct results.
The gross volume (total_volume) is correct, but the net_volume is a bit off.
I'm subtracting total_volume by net_volume, but the result is different than what I see on the Stripe dashboard.
Any ideas on how to calculate the Net volume from sales?
I need to get the gross/net volumes as seen on the Stripe dashboard using the Stripe API.