4. INVENTORIES

Inventories include the following:

	June 30, 2015		December 31, 2014
	(thousands of dollars)
Raw material	$	2,930	$	2,826
Work in process		76		49
Finished products		12,052		9,940
Total inventory	$	15,058	$	12,815

The difference between the calculated value of inventory under the FIFO and LIFO bases generates either a recorded LIFO reserve (i.e., where FIFO value exceeds the LIFO value) or an unrecorded negative LIFO reserve (i.e., where LIFO value exceeds the FIFO value). In the latter case, in order to ensure that inventory is reported at the lower of cost or market and in accordance with ASC 330-10, we do not increase the stated value of our inventory to the LIFO value.

At June 30, 2015, and December 31, 2014, LIFO value of petrochemical inventory exceeded FIFO; therefore, in accordance with the above policy, no LIFO reserve was recorded.

Inventory serves as collateral for our amended and restated loan agreement. See Note 8.

Inventory included petrochemical products in transit valued at approximately $2.8 million and $3.5 million at June 30, 2015, and December 31, 2014, respectively.